Got a packet bigger than ‘max_allowed_packet’ bytes mysql
set global max_allowed_packet=1000000000;
set global net_buffer_length=1000000;
set this from putty.
set-variable=record_buffer=16M
set this in my.cnf
Agile Project Management Tools
Filed under: Agile, Agile Project Management Tools, Agile Tools, Featured
Agile Project Management Tools
- XPlanner
- Agilo
- Agilefant
- IceScrum
- XPWeb
- XPStoryStudio
XPlanner
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Reviews & Opinions
Using XPlanner in real project March 20, 2004 Good opinion April 20, 2006
Agilo
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Interesting web-based tool. The tool is under active development (latest version July 27, 2008). It has some really nice concepts on board. Planning poker powers user stories estimation. Stories represented by cards and there are several useful filters presets. When you add a user story it has template As … I want … In order to … which is nice and helpful.
IceScrum is hard from the beginning, but it has nice features set and can be adopted by agile team. It seems it is the best open source agile project management tool so far.
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Agilefant is a web-based tool written on Java and the tool is under active development. It is quite feature rich and allows to create products, projects, iterations, themes and user stories, has time tracking, burn down chart, some people allocations management. It works pretty fast.
The missing features are release and iteration planning. The tool does not have the concept of releases at all and that is strange, since it has products! Almost no reporting, and poor customization. It does not support points units for planning (quite strange for agile tool). User interface has too few screens and some screens looks overburdened (like default project screen which contains project details, themes, backlog, iterations with all details). There are some usability issues, but in general tool is quite easy to grasp. It does not look like a complicated solution. You may try Agilefant for small projects, I don’t think it will be convenient for large projects with 20+ people.
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The only tool written on PHP. Has quite weird user interface, but quite a lot features. Demo is broken, so some features maybe do not work. The tool does not look as ready for production use in can’t be used for agile project management in large teams
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XPStoryStudio
From the first sight, XPStoryStudio may evolve into good tool, but in reality it was released in beta in 2004 and development stopped after beta release. So if you are not satisfied with current functionality there are no chances to change anything. Tool by itself is quite crude. Some things are good like iterations and user stories with tasks, but usability and user focused functionality is quite poor
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Configuring Windows 2000 IIS for CGI
· Install Windows Internet Information Server (IIS) (Windows XP screen shots)
- Start > Settings > Control Panel > Add/Remove Programs
- Add/Remove Windows Components
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Check the box for Internet Information Server (IIS); click the “Details…” button to select IIS components: |
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These are the components I installed, however you should not need FTP or SMTP if you only want to test CGI scripts: |
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Test the Server
- Assumptions:
- %SystemDrive% = C: <!–
- %SystemRoot% = C:WINNT –>
- %UserDomain% = LOCALHOST
Use the SET command in a Command Prompt window to check your settings.
Make applicable adjustments if %SystemDrive% or %UserDomain% have different values on your system.
- Create a simple HTML document in the default server directory.
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server_test.html in the default server directory C:Inetpubwwwroot |
<html>
<head>
<title>Server Test</title>
<!-- server_test.html -->
</head>
<body>
The server is working
</body>
</html>
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- Enter http://localhost/server_test.html in your browser to test the server
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If the IIS is installed and working you should see your test document displayed in the browser: |
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le="color:rgb(31,73,125);font-size:11px;">
· [TOP]
Install Perl
Download a current Perl binary distribution from www.activestate.com
The following are direct download links for ActiveState’s binaries for recent major versions of Perl. You may want to install more than one version depending on your need/desire to have a version compatible with the Perl you use on a Unix system.
- Perl 5.005_03 — ActiveState Build 522
5.3 Mb download - Perl 5.6.1 — ActiveState Build 635
8.6 Mb download - Perl 5.8.0 — ActiveState Build 806
11.3 Mb download
Other ActiveState links:
See Introduction to Perl for additional information about installing ActivePerl and other Perl binary distributions on Windows operating systems.
Configure the Server
- See assumptions under “Test the Server” and make adjustments as necessary
- You must be logged on as Administrator to configure IIS
- The default location for CGI scripts is C:InetpubScripts
- The URL to access scripts is http://localhost/scripts/script_name
- Start > Settings > Control Panel > Administrative Tools Internet Services Manager
Note: You may find it convenient to drag the Internet Services Manager menu item to the Desktop with the right mouse button and create a shortcut. - Click on the “+” to expand *localhost in the left pane
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Right-click and select Start or Stop as required to start or stop services. |
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- You only need Default Web Site to test CGI scripts. For security reasons you probably want to stop the services except when you are testing scripts so your server is not open to the Internet if you have an “always on” connection.
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Click on Default Web Site in the left pane to expand all the items in the right pane; right-click Click the “Create” button in the Virtual Directory tab so that the “Configuration” button is available (the “Create” button will change to “Remove”: |
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- Click the “Configuration” button and look for Perl file extensions in the App Mappings tab (usually .pl and .plx)
If you are using a Perl binary other than ActiveState, or if you installed ActivePerl from a ZIP file rather than the Windows installer, the extensions for Perl source files will probably not be present, in which case use the “Add” button to add a new mapping
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Select the .pl extension and click the “Edit” button or, if no Perl extensions were listed, click the “Add” button. |
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Edit or Add a new Application Extension Mapping as follows: |
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j. Notes:
- Edit the path to your Perl executable as required.
You may have multiple Perl installations; edit the path to reflect the installation/version you are currently using. - The ActivePerl installation does not include the -T switch to perl.exe as shown; however it must be part of the command line if you use it in the shebang line in your scripts.
If you are adding a new extension mapping be sure to include the -T switch. - If adding a new Application Extension Mapping be sure to enter the fields exactly as shown. Note in particular the arguments “%s” %s. I cannot find any definitive documentation for the syntax, but this is what works.
Test the Server and CGI
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Create a simple Perl script named cgi_test.pl in C:InetpubScripts as follows: |
#!/usr/bin/perl -T
# cgi_test.pl
use warnings;
print "content-type: text/htmlnn";
# Important! extra blank line after header
print "CGI is working";
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- Enter http://localhost/scripts/cgi_test.pl in your browser
If CGI and the Perl script are working you should see the following displayed in the browser:
c. Notes:
- Under Windows and IIS the path information in the shebang line is not required or used;
#!perl -T
is perfectly valid. - However. if you are testing scripts that will ultimately be uploaded to a Unix server you may want to use the same shebang that your Unix server requires, such as
#!/usr/bin/perl -T
Windows will read the command line switches and ignore the path.
Internet Services Manager “Run As” Shortcut
You want to be able to manage IIS, such as starting and stopping services, but do not want to log off your user account, log on as Administrator to do a simple task, then log off and back on to your user account again. And you definitely do not want to do your daily development work in the Administrator account.
You could navigate to Internet Services Manager via the Start Menu, press the shift key while right-clicking on the Internet Services Manager menu item, and get the “Run As” prompt; however, better to create a shortcut to do all that for you.
- From your normal user account create a shortcut to Internet Services Manager
- Start > Settings > Control Panel > Administrative Tools > Internet Services Manager
- Holding down the right mouse button drag the Internet Services Manager menu item onto the Desktop and select “Create Shortcut(s) Here”
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Right-click on the shortcut, select properties, and check the “Advanced” button. Check “Run with different credentials” |
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When you use the shortcut you will be prompted for the user account and password to run the application. The default is Administrator, which is usually what you want. |
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Create new IIS Virtual Directory
You want to be able to create, add, and edit scripts, however you do not want to do your development work under the Administrator account; and you do not want to log out of your user account, log on as Administrator to copy files to the default scripts folder, then log back on to your user account. Solution: create a IIS Virtual Directory that is accessible from your user account.
- Open the Internet Services Manager snap-in and create a new Virtual Directory
- Right-click on Default Web Site in the l
eft pane, select New > Virtual Directory
- Work through the Virtual Directory Creation Wizard
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Choose a Virtual Directory Alias (this will be the path following the LOCALHOST domain: http://localhost/usr-cgi |
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Choose a Web Site Content Directory where you have access from your normal user account. |
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When you get to the Access Permissions step in the Wizard be sure to check the “Execute…” box in addition to the Read and Run boxes already checked by default. |
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- After you have created the new virtual directory you must also configure it just like the Default Directory above. See 4. Configure the Server above.
How to make Apache run ASP.NET / ASP.NET 2.0
Even worked with ASP.NET 2.0 Site !
Following are the instruction to make Asp.Net work under apache:
– Install Apache 2.0.54
– Install Mod_AspDotNet
– Add at the end of C:Program FilesApache GroupApache2confhttpd.conf the following lines
#asp.net
LoadModule aspdotnet_module “modules/mod_aspdotnet.so”
AddHandler asp.net asax ascx ashx asmx aspx axd config cs csproj licx rem resources resx soap vb vbproj vsdisco webinfo
<IfModule mod_aspdotnet.cpp>
# Mount the ASP.NET /asp application
AspNetMount /SampleASP “c:/SampleASP”
#/SampleASP is the alias name for asp.net to execute
#”c:/SampleASP” is the actual execution of files/folders in that location
# Map all requests for /asp to the application files
Alias /SampleASP “c:/SampleASP”
#maps /SampleASP request to “c:/SampleASP”
#now to get to the /SampleASP type http://localhost/SampleASP
#It’ll redirect http://localhost/SampleASP to “c:/SampleASP”
# Allow asp.net scripts to be executed in the /SampleASP example
<Directory “c:/SampleASP”>
Options FollowSymlinks ExecCGI
Order allow,deny
Allow from all
DirectoryIndex index.htm index.aspx
#default the index page to .htm and .aspx
</Directory>
# For all virtual ASP.NET webs, we need the aspnet_client files
# to serve the client-side helper scripts.
AliasMatch /aspnet_client/system_web/(d+)_(d+)_(d+)_(d+)/(.*) “C:/Windows/Microsoft.NET/Framework/v$1.$2.$3/ASP.NETClientFiles/$4″
<Directory “C:/Windows/Microsoft.NET/Framework/v*/ASP.NETClientFiles”>
Options FollowSymlinks
Order allow,deny
Allow from all
</Directory>
</IfModule>
#asp.net
– Create a directory c:SampleASP and insert in it the index.aspx
– Restart apache server :
Start-> Apache HTTP Server 2.0.54 ->
Control Apache Server -> Restart
– Open Explorer and navigate to http://localhost/SampleASP/index.aspx
If everything worked fine you should get a nice asp.net page working.
— index.aspx —
<%@ Page Language=”VB” %>
<html>
<head>
<link rel=”stylesheet”href=”intro.css”>
</head>
<body>
<center>
<form action=”index.aspx” method=”post”>
<h3> Name: <input id=”Name” type=text>
Category: <select id=”Category” size=1>
<option>One</option>
<option>Two</option>
<option>Three</option>
</select>
</h3>
<input type=submit value=”Lookup”>
<p>
<% Dim I As Integer
For I = 0 to 7 %>
<font size=”<%=I%>”> Sample ASP.NET TEST</font> <br>
<% Next %>
</form>
</center>
</body>
</html>
Set Cron in Ubuntu (Linux)
What is Cron?
Cron is a daemon used for scheduling tasks to be executed at a certain time. Each user has a crontab file, allowing them to specify actions and times that they should be executed. There is also a system crontab, allowing tasks such as log rotation and locate database updating to be done regularly.
The following directions tell you how to set up scheduled tasks the traditional way using the command line, but it is much easier to use the Gnome Scheduled tasks tool in System –> Preferences
What is Crontab?
A crontab is a simple text file that holds a list of commands that are to be run at specified times. These commands, and their related run times, are controlled by the cron daemon and are executed in the system’s background. More information can be found by viewing the crontab’s man page.
Using Cron
To use cron, simply add entries to your crontab file.
Crontab Sections
Each of the sections is separated by a space, with the final section having one or more spaces in it. No spaces are allowed within Sections 1-5, only between them. Sections 1-5 are used to indicate when and how often you want the task to be executed. This is how a cron job is laid out:
minute (0-59), hour (0-23, 0 = midnight), day (1-31), month (1-12), weekday (0-6, 0 = Sunday), command
01 04 1 1 1 /usr/bin/somedirectory/somecommand
The above example will run /usr/bin/somedirectory/somecommand at 4:01am on January 1st plus every Monday in January. An asterisk (*) can be used so that every instance (every hour, every weekday, every month, etc.) of a time period is used. Code:
01 04 * * * /usr/bin/somedirectory/somecommand
The above example will run /usr/bin/somedirectory/somecommand at 4:01am on every day of every month.
Comma-seperated values can be used to run more than one instance of a particular command within a time period. Dash-seperated values can be used to run a command continuously. Code:
01,31 04,05 1-15 1,6 * /usr/bin/somedirectory/somecommand
The above example will run /usr/bin/somedirectory/somecommand at 01 and 31 past the hours of 4:00am and 5:00am on the 1st through the 15th of every January and June.
The “/usr/bin/somedirectory/somecommand” text in the above examples indicates the task which will be run at the specified times. It is recommended that you use the full path to the desired commands as shown in the above examples. Enter which somecommand in the terminal to find the full path to somecommand. The crontab will begin running as soon as it is properly edited and saved.
Crontab Options
- The -l option causes the current crontab to be displayed on standard output.
- The -r option causes the current crontab to be removed.
- The -e option is used to edit the current crontab using the editor specified by the EDITOR environment variable.
After you exit from the editor, the modified crontab will be checked for accuracy and, if there are no errors, installed automatically. The file is stored in /var/spool/cron/crontabs but should only be edited via the crontab command.
Further Considerations
The above commands are stored in a crontab file belonging to your user account and executed with your level of permissions. If you want to regularly run a command requiring a greater level of permissions, set up a root crontab file using:
sudo crontab -e
Depending on the commands being run, you may need to expand the root users PATH variable by putting the following line at the top of their crontab file:
PATH=/usr/sbin:/usr/bin:/sbin:/bin
It is sensible to test that your cron jobs work as intended. One method for doing this is to set up the job to run a couple of minutes in the future and then check the results before finalising the timing. You may also find it useful to put the commands into script files that log their success or failure, eg:
echo "Nightly Backup Successful: $(date)" >> /tmp/mybackup.log
For more information, see the man pages
for cron and crontab (man is detailed on the BasicCommands page). If your machine is regularly switched off, you may also be interested in at and anacron, which provide other approaches to scheduled tasks. For example, anacron offers simple system-wide directories for running commands hourly, daily, weekly, and monthly. Scripts to be executed in said times can be placed in /etc/cron.hourly/, /etc/cron.daily/, /etc/cron.weekly/, and /etc/cron.monthly/. All scripts in each directory are run as root, and a specific order to running the scripts can be specified by prefixing the scripts’ filenames with numbers (see the man page for run-parts for more details). Although the directories contain periods in their names, run-parts will not accept a file name containing one and will fail silently when encountering them (bug #38022). Either rename the file or use a symlink (without a period) to it instead.
Advanced Crontab
The Crontabs discussed above are user crontabs. Each of the above crontabs is associated with a user, even the system crontab which is associated with the root user. There are two other types of crontab.
Firstly, as mentioned above anacron uses the run-parts command and /etc/cron.hourly, /etc/cron.weekly, and /etc/cron.monthly directories. However anacron itself is invoked from the /etc/crontab file. This file could be used for other cron commands, but probably shouldn’t be. Here’s an example line from a ficticious /etc/crontab:
00 01 * * * rusty /home/rusty/rusty-list-files.sh
This would run Rusty’s command script as user rusty from his home directory. However, it is not usual to add commands to this file. While an experienced user should know about it, it is not recommended that you add anything to /etc/crontab. Apart from anything else, this could cause problem if the /etc/crontab file is affected by updates! Rusty could lose his command.
The second type of crontab is to be found in /etc/cron.d. Within the directory are small named crontabs. The directory is often used by packages, and the small crontabs allows a user to be associated with the commands in them.
Instead of adding a line to /etc/crontab which Rusty knows is not a good idea, Rusty might well add a file to /etc/cron.d with the name rusty, containing his cron line above. This would not be affected by updates but is a well known location.
When would you use these alternate crontab locations? Well, on a single user machine or a shared machine such as a school or college server, a user crontab would be the way to go. But in a large IT department, where several people might look after a server, then /etc/cron.d is probably the best place to install crontabs – it’s a central point and saves searching for them!
You may not need to look at /etc/crontab or /etc/cron.d, let alone edit them by hand. But an experienced user should perhaps know about them and that the packages that he/she installs may use these locations for their crontabs.
Tips
crontab -e uses the EDITOR environment variable. to change the editor to your own choice just set that. You may want to set EDITOR in you .bashrc because many commands use this variable. Let’s set the EDITOR to nano a very easy editor to use:
export EDITOR=nano
There are also files you can edit for system-wide cron jobs. The most common file is located at /etc/crontab, and this file follows a slightly different syntax than a normal crontab file. Since it is the base crontab that applies system-wide, you need to specify what user to run the job as; thus, the syntax is now:
minute(s) hour(s) day(s)_of_month month(s) day(s)_of_week user command
It is recommended, however, that you try to avoid using /etc/crontab unless you need the flexibility offered by it, or if you’d like to create your own simplified anacron-like system using run-parts for example. For all cron jobs that you want to have run under your own user account, you should stick with using crontab -e to edit your local cron jobs rather than editting the system-wide /etc/crontab.
It is possible to run gui applications via cronjobs. This can be done by telling cron which display to use.
00 06 * * * env DISPLAY=:0. gui_appname
The env DISPLAY=:0. portion will tell cron to use the current display (desktop) for the program “gui_appname”.
And if you have multiple monitors, don’t forget to specify on which one the program is to be run. For example, to run it on the first screen (default screen) use :
00 06 * * * env DISPLAY=:0.0 gui_appname
The env DISPLAY=:0.0 portion will tell cron to use the first screen of the current display for the program “gui_appname”.
Crontab Example
Below is an example of how to setup a crontab to run updatedb, which updates the slocate database: Open a term, type “crontab -e” (without the double quotes) and press enter. Type the following line, substituting the full path of the application you wish to run for the one shown below, into the editor:
45 04 * * * /usr/bin/updatedb
Save your changes and exit the editor.
Crontab will let you know if you made any mistakes. The crontab will be installed and begin running if there are no errors. That’s it. You now have a cronjob setup to run updatedb, which updates the slocate database, every morning at 4:45.
Note: The double-ampersand (&&) can also be used in the “command” section to run multiple commands consecutively.
45 04 * * * /usr/sbin/chkrootkit && /usr/bin/updatedb
The above example will run chkrootkit followed by updatedb at 4:45am daily – providing you have all listed apps installed.
Top 10 URLS
1 google.com 135M+ U.S. monthly people. The site attracts a more affluent, more educated audience. >74 pronto.com 11M+ U.S. monthly people. The site appeals to a skewing older group.
2 yahoo.com 124M+ U.S. monthly people. The site appeals to a more educated crowd.
3 msn.com 91M+ U.S. monthly people. The site caters to a adult, more educated audience.
4 live.com 90M+ U.S. monthly people. The site appeals to a more educated crowd.
5 wikipedia.org 77M+ U.S. monthly people. The site is popular among a more educated, younger audience.
6 aol.com 75M+ U.S. monthly people. The site caters to a very slightly female biased, younger crowd.
7 youtube.com 70M+ U.S. monthly people. The site appeals to a more youthful following.
8 myspace.com 67M+ U.S. monthly people. The site is popular among a more female, teen and young adult audience.
9 microsoft.com 66M+ U.S. monthly people. The site attracts a skewing older audience.
10 ebay.com 59M+ U.S. monthly people. The site is popular among a more affluent, slightly male slanted, adult following.
11 amazon.com 46M+ U.S. monthly people. The site appeals to a more educated following.
12 facebook.com 45M+ U.S. monthly people. The site appeals to a more affluent, teen and young adult, very slightly female biased following.
13 about.com 45M+ U.S. monthly people. The site is popular among a very slightly female biased audience.
14 mapquest.com 45M+ U.S. monthly people. The site appeals to a slightly female slanted, more educated, more affluent group.
15 blogspot.com 43M+ U.S. monthly people. The site attracts a more educated following.
16 nextag.com 43M+ U.S. monthly people. The site is popular among a more affluent, more educated, skewing older audience.
17 craigslist.org 40M+ U.S. monthly people. The site attracts a very slightly male biased, fairly wealthy audience.
18 ask.com 39M+ U.S. monthly people. The site appeals to a slightly more female than male audience.
19 answers.com 37M+ U.S. monthly people. The site appeals to a more youthful, more educated following.
20 adobe.com 34M+ U.S. monthly people. The site attracts a slightly female slanted, skewing older audience.
21 photobucket.com 34M+ U.S. monthly people. The site appeals to a slightly more female than male, teen audience.
22 go.com 34M+ U.S. monthly people. The site appeals to a more affluent group.
23 reference.com 32M+ U.S. monthly people. The site caters to a teen, more educated audience.
24 wordpress.com 31M+ U.S. monthly people. The site is popular among a youthful crowd.
25 information.com 30M+ U.S. monthly people. The site is popular among a slightly female slanted crowd.
26 cnn.com 29M+ U.S. monthly people. The site attracts a more educated, rather male, fairly wealthy audience.
27 windows.com 29M+ U.S. monthly people. The site attracts a skewing older following.
28 walmart.com 26M+ U.S. monthly people. The site caters to a very slightly female biased audience.
29 paypal.com 26M+ U.S. monthly people. The site caters to a adult, fairly wealthy audience.
30 blogger.com 24M+ U.S. monthly people. The site caters to a more educated audience.
31 flickr.com 23M+ U.S. monthly people. The site appeals to a slightly male slanted audience.
32 att.com 22M+ U.S. monthly people. The site is popular among a very slightly female biased audience.
33 target.com 21M+ U.S. monthly people. The site appeals to a somewhat female audience.
34 imdb.com 21M+ U.S. monthly people.
35 comcast.net 21M+ U.S. monthly people. The site appeals to a more affluent, skewing older, very slightly female biased audience.
36 geocities.com 21M+ U.S. monthly people.
37 bizrate.com 20M+ U.S. monthly people. The site caters to a skewing older, more affluent audience.
38 bankofamerica.com 18M+ U.S. monthly people. The site attracts a adult, more affluent, more educated crowd.
39 yellowpages.com 18M+ U.S. monthly people. The site attracts a adult, rather female following.
40 smileycentral.com 17M+ U.S. monthly people. The site is popular among a younger, more female following.
41 webmd.com 16M+ U.S. monthly people. The site attracts a skewing older, more female audience.
42 nytimes.com 16M+ U.S. monthly people. The site appeals to a skewing older, fairly wealthy, very slightly male biased, more educated audience.
43 ehow.com 15M+ U.S. monthly people. The site attracts a slightly more female than male audience.
44 pbs.org 15M+ U.S. monthly people. The site caters to a more educated audience.
45 apple.com 15M+ U.S. monthly people. The site appeals to a younger, fairly wealthy, very slightly female biased group.
46 weather.com 15M+ U.S. monthly people. The site attracts a fairly wealthy, adult, more educated audience.
47 whitepages.com 14M+ U.S. monthly people. The site caters to a skewing older, very slightly female biased following.
48 yahoo.net 14M+ U.S. monthly people. The site attracts a more educated, more affluent, adult audience.
49 classmates.com 14M+ U.S. monthly people. The site is popular among a slightly more female than male, skewing older group.
50 nbc.com 14M+ U.S. monthly people. The site caters to a slightly female slanted crowd.
51 chase.com 14M+ U.S. monthly people. The site attracts a adult, slightly female slanted, more affluent, more educated audience.
52 careerbuilder.com 14M+ U.S. monthly people. The site is popular among a slightly female slanted group.
53 mywebsearch.com 14M+ U.S. monthly people. The site appeals to a largely female audience.
54 evite.com 13M+ U.S. monthly people. The site caters to a somewhat wealthy, more educated, very slightly female biased crowd.
55 monster.com 13M+ U.S. monthly people. The site caters to a very slightly female biased following.
56 capitalone.com 13M+ U.S. monthly people. The site is popular among a very slightly female biased, adult audience.
57 download.com 13M+ U.S. monthly people. The site is popular among a very slightly male biased audience.
58 usps.com 13M+ U.S. monthly people. The site caters to a adult, more educated following.
59 barackobama.com 13M+ U.S. monthly people. The site appeals to a more African American, fairly wealthy, skewing older, more educated, somewhat female crowd.
60 newsweek.com 12M+ U.S. monthly people. The site is popular among a fairly wealthy, more educated, slightly more male than female, skewing older following.
61 verizonwireless.com 12M+ U.S. monthly people. The site is popular among a slightly female slanted, fairly wealthy crowd.
62 bestbuy.com 12M+ U.S. monthly people. The site attracts a very slightly male biased crowd.
63 tripod.com 12M+ U.S. monthly people.
64 shopzilla.com 12M+ U.S. monthly people. The site appeals to a skewing older, slightly female slanted crowd.
65 wellsfargo.com 12M+ U.S. monthly people. The site appeals to a slightly female slanted crowd.
66 merriam-webster.com 12M+ U.S. monthly people. The site attracts a more educated, fairly wealthy audience.
67 hp.com 12M+ U.S. monthly people. The site attracts a skewing older audience.
68 metacafe.com 12M+ U.S. monthly people. The site appeals to a slightly male slanted, younger crowd.
69 comcast.com 12M+ U.S. monthly people. The site is popular among a adult, slightly female slanted, fairly wealthy audience.
70 linkedin.com 12M+ U.S. monthly people. The site caters to a very slightly male biased, middle aged, more affluent, more educated following.
71 digg.com 11M+ U.S. monthly people. The site appeals to a more male audience.
72 foxnews.com 11M+ U.S. monthly people. The site is popular among a fairly wealthy, more educated, slightly more male than female, skewing older audience.
73 reunion.com 11M+ U.S. monthly people. The site attracts a rather female, skewing older audience.
75 typepad.com 11M+ U.S. monthly people. The site caters to a more educated, more affluent audience.
76 jcpenney.com 11M+ U.S. monthly people. The site appeals to a primarily female, skewing older following.
77 nih.gov 11M+ U.S. monthly people. The site appeals to a more educated, skewing older, somewhat female audience.
78 netflix.com 10M+ U.S. monthly people. The site caters to a adult, very slightly female biased, more educated audience.
79 wikimedia.org 10M+ U.S. monthly people. The site caters to a slightly more male than female, teen, more educated audience.
80 addresses.com 10M+ U.S. monthly people. The site appeals to a very slightly female biased, skewing older audience.
81 ups.com 10M+ U.S. monthly people. The site is popular among a adult, more affluent following.
82 symantec.com 10M+ U.S. monthly people. The site caters to a skewing older crowd.
83 smarter.com 10M+ U.S. monthly people. The site caters to a slightly more female than male, 50+ audience.
84 dell.com 10M+ U.S. monthly people. The site is popular among a skewing older, more educated audience.
85 ezinearticles.com 10.0M+ U.S. monthly people.
86 allrecipes.com 9.8M+ U.S. monthly people. The site caters to a mostly female group.
87 findstuff.com 9.8M+ U.S. monthly people. The site caters to a slightly female slanted audience.
88 time.com 9.8M+ U.S. monthly people. The site is popular among a somewhat male, more educated, more affluent, skewing older audience.
89 people.com 9.7M+ U.S. monthly people. The site caters to a more affluent, slightly female slanted crowd.
90 huffingtonpost.com 9.7M+ U.S. monthly people. The site attracts a more educated, middle aged, rather male, more affluent crowd.
91 gamespot.com 9.5M+ U.S. monthly people. The site appeals to a more male, teen audience.
92 washingtonpost.com 9.5M+ U.S. monthly people. The site appeals to a skewing older, fairly wealthy, slightly more male than female, more educated audience.
93 webcrawler.com 9.4M+ U.S. monthly people.
94 circuitcity.com 9.4M+ U.S. monthly people. The site attracts a adult audience.
95 job.com 9.3M+ U.S. monthly people. The site caters to a more African American, somewhat female group.
96 hulu.com 9.3M+ U.S. monthly people. The site caters to a slightly male slanted audience.
97 ticketmaster.com 9.0M+ U.S. monthly people. The site attracts a slightly female slanted, more affluent following.
98 overstock.com 9.0M+ U.S. monthly people. The site attracts a rather female, more affluent, skewing older following.
99 local.com 8.9M+ U.S. monthly people. The site caters to a skewing older, very slightly female biased audience.
100 nfl.com 8.9M+ U.S. monthly people. The site is popular among a more male, more affluent group.
(mysql.info)Command-line options
mysqld Command-line Options
---------------------------
`mysqld' accepts the following command-line options:
`--ansi'
Use ANSI SQL syntax instead of MySQL syntax. Note: ANSI mode.
`-b, --basedir=path'
Path to installation directory. All paths are usually resolved
relative to this.
`--big-tables'
Allow big result sets by saving all temporary sets on file. It
solves most 'table full' errors, but also slows down the queries
where in-memory tables would suffice. Since Version 3.23.2, MySQL
is able to solve it automatically by using memory for small
temporary tables and switching to disk tables where necessary.
`--bind-address=IP'
IP address to bind to.
`--character-sets-dir=path'
Directory where character sets are. Note: Character sets.
`--chroot=path'
Chroot `mysqld' daemon during startup. Recommended security
measure. It will somewhat limit `LOAD DATA INFILE' and `SELECT ...
INTO OUTFILE' though.
`--core-file'
Write a core file if `mysqld' dies. For some systems you must also
specify `--core-file-size' to `safe_mysqld'. *Note `safe_mysqld':
safe_mysqld.
`-h, --datadir=path'
Path to the database root.
`--default-character-set=charset'
Set the default character set. Note: Character sets.
`--default-table-type=type'
Set the default table type for tables. Note: Table types.
`--debug[...]='
If MySQL is configured with `--with-debug', you can use this
option to get a trace file of what `mysqld' is doing. Note:
Making trace files.
`--delay-key-write-for-all-tables'
Don't flush key buffers
between writes for any `MyISAM' table.
Note: Server parameters.
`--enable-locking'
Enable system locking. Note that if you use this option on a
system which a not fully working lockd() (as on Linux) you will
easily get mysqld to deadlock.
`--enable-named-pipe'
Enable support for named pipes (only on NT/Win2000/XP).
`-T, --exit-info'
This is a bit mask of different flags one can use for debugging the
mysqld server; One should not use this option if one doesn't know
exactly what it does!
`--flush'
Flush all changes to disk after each SQL command. Normally MySQL
only does a write of all changes to disk after each SQL command
and lets the operating system handle the syncing to disk. Note:
Crashing.
`-?, --help'
Display short help and exit.
`--init-file=file'
Read SQL commands from this file at startup.
`-L, --language=...'
Client error messages in given language. May be given as a full
path. Note: Languages.
`-l, --log[=file]'
Log connections and queries to file. Note: Query log.
`--log-isam[=file]'
Log all ISAM/MyISAM changes to file (only used when debugging
ISAM/MyISAM).
`--log-slow-queries[=file]'
Log all queries that have taken more than `long_query_time'
seconds to execute to file. Note: Slow query log.
`--log-update[=file]'
Log updates to `file.#' where `#' is a unique number if not given.
Note: Update log.
`--log-long-format'
Log some extra information to update log. If you are using
`--log-slow-queries' then queries that are not using indexes are
logged to the slow query log.
`--low-priority-updates'
Table-modifying operations (`INSERT'/`DELETE'/`UPDATE') will have
lower priority than selects. It can also be done via `{INSERT |
REPLACE | UPDATE | DELETE} LOW_PRIORITY ...' to lower the priority
of only one query, or by `SET OPTION SQL_LOW_PRIORITY_UPDATES=1'
to change the priority in one thread. Note: Table locking.
`--memlock'
Lock the `mysqld' process in memory. This works only if your
system supports the `mlockall()' system call (like Solaris). This
may help if you have a problem where the operating system is
causing `mysqld' to swap on disk.
`--myisam-recover [=option[,option...]]] where option is any combination'
of `DEFAULT', `BACKUP', `FORCE' or `QUICK'. You can also set this
explicitely to `""' if you want to disable this option. If this
option is used, `mysqld' will on open check if the table is marked
as crashed or if if the table wasn't closed properly. (The last
option only works if you are running with `--skip-locking'). If
this is the case `mysqld' will run check on the table. If the
table was corrupted, `mysqld' will attempt to repair it.
The following options affects how the repair works.
DEFAULT The same as not giving any option to
`--myisam-recover'.
BACKUP If the data table was changed during recover,
save a backup of the
`table_name.MYD' data file as
`table_name-datetime.BAK'.
FORCE Run recover even if we will loose more than
one row from the .MYD file.
QUICK Don't check the rows in the table if there
isn't any delete blocks.
Before a table is automatically repaired, MySQL will add a note
about this in the error log. If you want to be able to recover
from most things without user intervention, you should use the
options `BACKUP,FORCE'. This will force a repair of a table even
if some rows would be deleted, but it will keep the old data file
as a backup so that you can later examine what happened.
`--pid-file=path'
Path to pid file used by `safe_mysqld'.
`-P, --port=...'
Port number to listen for TCP/IP connections.
`-o, --old-protocol'
Use the 3.20 protocol for compatibility with some very old clients. *Note Upgrading-from-3.20::.
`--one-thread'
Only use one thread (for debugging under Linux). Note: Debugging
server.
`-O, --set-variable var=option'
Give a variable a value. `--help' lists variables. You can find a
full description for all variables in the `SHOW VARIABLES' section
in this manual. Note: SHOW VARIABLES. The tuning server
parameters section includes information of how to optimize these.
Note: Server parameters.
`--safe-mode'
Skip some optimize stages. Implies `--skip-delay-key-write'.
`--safe-show-database'
Don't show databases for which the user doesn't have any
privileges.
`--safe-user-create'
If this is enabled, a user can't create new users with the GRANT
command, if the user doesn't have `INSERT' privilege to the
`mysql.user' table or any column in this table.
`--skip-concurrent-insert'
Turn off the ability to select and insert at the same time on
`MyISAM' tables. (This is only to be used if you think you have
found a bug in this feature).
`--skip-delay-key-write'
Ignore the `delay_key_write' option for all tables. Note: Server
parameters.
`--skip-grant-tables'
This option causes the server not to use the privilege system at
all. This gives everyone _full access_ to all databases! (You
can tell a running server to start using the grant tables again by
executing `mysqladmin flush-privileges' or `mysqladmin reload'.)
`--skip-host-cache'
Never use host name cache for faster name-ip resolution, but query
DNS server on every connect instead. Note: DNS.
`--skip-locking'
Don't use system locking. To use `isamchk' or `myisamchk' you must
shut down the server. Note: Stability. Note that in MySQL
Version 3.23 you can use `REPAIR' and `CHECK' to repair/check
`MyISAM' tables.
`--skip-name-resolve'
Hostnames are not resolved. All `Host' column values in the grant
tables must be IP numbers or `localhost'. Note: DNS.
`--skip-networking'
Don't listen for TCP/IP connections at all. All interaction with
`mysqld' must be made via Unix sockets. This option is highly
recommended for systems where only local requests are allowed.
Note: DNS.
`--skip-new'
Don't use new, possible wrong routines. Implies
`--skip-delay-key-write'. This will also set default table type
to `ISAM'. Note: ISAM.
`--skip-symlink'
Don't delete or rename files that a symlinked file in the data
directory points to.
`--skip-safemalloc'
If MySQL is configured with `--with-debug=full', all programs will
check the memory for overruns for every memory allocation and
memory freeing. As this checking is very slow, you can avoid
this, when you don't need memory checking, by using this option.
`--skip-show-database'
Don't allow 'SHOW DATABASE' commands, unless the user has *process*
privilege.
`--skip-stack-trace'
Don't write stack traces. This option is useful when you are
running `mysqld' under a debugger. Note: Debugging server.
`--skip-thread-priority'
Disable using thread priorities for faster response time.
`--socket=path'
Socket file to use for local connections instead of default
`/tmp/mysql.sock'.
`--sql-mode=option[,option[,option...]]'
Option can be any combination of: `REAL_AS_FLOAT',
`PIPES_AS_CONCAT', `ANSI_QUOTES', `IGNORE_SPACE', `SERIALIZE',
`ONLY_FULL_GROUP_BY'. It can also be empty (`""') if you want to
reset this
.
By specifying all of the above options is same as using -ansi.
With this option one can turn on only needed SQL modes. Note: ANSI
mode.
`transaction-isolation= { READ-UNCOMMITTED | READ-COMMITTED | REPEATABLE-READ | SERIALIZABLE }'
Sets the default transaction isolation level. Note: SET
TRANSACTION.
`-t, --tmpdir=path'
Path for temporary files. It may be useful if your default `/tmp'
directory resides on a partition too small to hold temporary
tables.
`-u, --user=user_name'
Run `mysqld' daemon as user `user_name'. This option is
_mandatory_ when starting `mysqld' as root.
`-V, --version'
Output version information and exit.
`-W, --warnings'
Print out warnings like `Aborted connection...' to the `.err' file.
Note: Communication errors.
Three easy ways to optimize your MySQL queries
Any database programmer will tell you that in high-traffic database-driven applications, a single badly-designed SQL query can significantly impact the overall performance of your application. Not only does such a query consume more database time than it ideally should, but it can have an exponential effect on the performance of other application components.
Optimizing query performance is as much a black art as a science, as heavily dependent on the developer’s intuition as on hard statistical performance data. Fortunately, databases likes MySQL come with some tools to aid the process, and this article discusses three of them briefly: using indexes, analyzing queries with EXPLAIN, and adjusting MySQL’s internal configuration.
#1: Using indexes
MySQL allows you to index database tables, making it possible to quickly seek to records without performing a full table scan first and thus significantly speeding up query execution. You can have up to 16 indexes per table, and MySQL also supports multi-column indexes and full-text search indexes.
Adding an index to a table is as simple as calling the CREATE INDEX command and specifying the field(s) to index. Listing A shows you an example:
Listing A
mysql> CREATE INDEX idx_username ON users(username);
Query OK, 1 row affected (0.15 sec)
Records: 1 Duplicates: 0 Warnings: 0
Here, indexing the username field of the users table ensures that SELECT queries which reference this field in their WHERE or HAVING clause will run a little faster than in the pre-indexed state. You can check that the index was created (Listing B) with the SHOW INDEX command:
Listing B
mysql> SHOW INDEX FROM users;
————–+————-+———–+————-+———-+——–+——+————+———+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
————–+————-+———–+————-+———-+——–+——+————+———+
| users | 1 | idx_username | 1 | username | A | NULL | NULL | NULL | YES | BTREE | |
————–+————-+———–+————-+———-+——–+——+————+———+
1 row in set (0.00 sec)
It’s important to note that indexes are a double-edged sword. Indexing every field of a table is usually unnecessary, and is quite likely to slow things down significantly when inserting or updating data because of the additional work MySQL has to do to rebuild the index each time. On the other hand, avoiding indexes altogether isn’t such a great idea either, because while this will speed up INSERTs, it will cause SELECT operations to slow down. There is thus always a trade-off to be made, and it’s wise to consider what the primary function of the table will be (data retrieval or data edit) when designing the indexing system.
#2: Optimizing query performance
When analyzing query performance, it’s also useful to consider the EXPLAIN keyword. This keyword, when placed in front of a SELECT query, describes how MySQL intends to execute the query and the number of rows it will need to process to successfully deliver a result set. To illustrate, consider the following simple example (Listing C):
Listing C
mysql> EXPLAIN SELECT city.name, city.district FROM city, country WHERE city.countrycode = country.code AND country.code = ‘IND’;
+—-+————-+———+——-+—————+———+———+——-+——+————-+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+—-+————-+———+——-+—————+———+———+——-+——+————-+
| 1 | SIMPLE | country | const | PRIMARY | PRIMARY | 3 | const | 1 | Using index |
| 1 | SIMPLE | city | ALL | NULL | NULL | NULL | NULL | 4079 | Using where |
+—-+————-+———+——-+—————+———+———+——-+——+————-+
2 rows in set (0.00 sec)
Here, the query is structured as a join between two tables and the EXPLAIN keyword describes how MySQL will process the join. It should be clear the current design will require MySQL to process only one record in the country table (which is indexed) but all 4079 records in the city table (which isn’t). This then suggests scope for improvement using other optimization tricks – for example, adding an index to the city table as follows (Listing D):
Listing D
mysql> CREATE INDEX idx_ccode ON city(countrycode);
Query OK, 4079 rows affected (0.15 sec)
Records: 4079 Duplicates: 0 Warnings: 0
And now, when you re-run the query with EXPLAIN, you’ll see a noticeable improvement (Listing E):
Listing E
mysql> EXPLAIN SELECT city.name, city.district FROM city, country WHERE city.countrycode = country.code AND country.code = ‘IND’;
+—-+————-+———+——-+—————+———–+———+——-+——+————-+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+—-+————-+———+——-+—————+———–+———+——-+——+————-+
| 1 | SIMPLE | country | const | PRIMARY | PRIMARY | 3 | const | 1 | Using index |
| 1 | SIMPLE | city | ref | idx_ccode | idx_ccode | 3 | const | 333 | Using where |
+—-+————-+———+——-+—————+———–+———+——-+——+————-+
2 rows in set (0.01 sec)
As this illustrates, MySQL now only needs to scan 333 records in the city table to produce a result set — a reduction of almost 90 percent! Naturally, this translates into faster query execution time and more efficient usage of database resources.
#3: Adjusting internal variables
MySQL is so open that it’s fairly easy to further fine-tune its default settings to obtain greater performance and stability. Some of the key variables that should be optimized are listed below.
- Altering Index Buffer Size (key_buffer)
This variable controls the size of the buffer used when handling table indices (both read and write operations). The MySQL manual recommends that this variable be increased “to as much as you can afford” to ensure you get the best performance on indexed tables, and recommends a value equivalent to about 25 percent of the total system memory. This is one of the more important MySQL configuration variables and if you’re interested in optimizing and improving performance, trying different values for the key_buffer_size variable is a good place to start. - Altering Table Buffer Size (read_buffer_size)
When a query requires a table to be scanned sequentially, MySQL allocates a memory buffer to this query. The read_buffer_size variable controls the size of this buffer. If you find that sequential scans are proceeding slowly, you can improve performance by increasing this value, and hence the size of the memory buffer. - Setting The Number Of Maximum Open Tables (table_cache)
This variable controls the maximum number of tables MySQL can have open at any one time, and thus controls the server’s ability to respond to incoming requests. This variable is closely related to the max_connections variables — increasing this value allows MySQL to keep a larger number of tables open, just as increasing max_connections increases the number of allowed connections. Consider altering this value if you have a high-volume server which receives queries on multiple different databases and tables. - Deciding A Time Limit For Long Queries (long_query_time)
MySQL comes with a so-called “slow query log”, which automatically logs all queries that do not end within a particular time limit. This log is useful to track inefficient or misbehaving queries, and to find targets for optimization algorithms. The long_query_time variable controls this maximum time limit, in seconds.
The previous discussion should give you some insight into three tools you can use to analyze and optimize your SQL queries, and help you squeeze better performance out of your application. Go on and try them out — and happy optimizing!
What is the maximum length of a URL?
Microsoft Internet Explorer (Browser)
Microsoft states that the maximum length of a URL in Internet Explorer is 2,083 characters, with no more than 2,048 characters in the path portion of the URL. In my tests, attempts to use URLs longer than this produced a clear error message in Internet Explorer.
Firefox (Browser)
After 65,536 characters, the location bar no longer displays the URL in Windows Firefox 1.5.x. However, longer URLs will work. I stopped testing after 100,000 characters.
Safari (Browser)
At least 80,000 characters will work. I stopped testing after 80,000 characters.
Opera (Browser)
At least 190,000 characters will work. I stopped testing after 190,000 characters. Opera 9 for Windows continued to display a fully editable, copyable and pasteable URL in the location bar even at 190,000 characters.
Apache (Server)
My early attempts to measure the maximum URL length in web browsers bumped into a server URL length limit of approximately 4,000 characters, after which Apache produces a “413 Entity Too Large” error. I used the current up to date Apache build found in Red Hat Enterprise Linux 4. The official Apache documentation only mentions an 8,192-byte limit on an individual field in a request.
Microsoft Internet Information Server
The default limit is 16,384 characters (yes, Microsoft’s web server accepts longer URLs than Microsoft’s web browser). This is configurable.
Perl HTTP::Daemon (Server)
Up to 8,000 bytes will work. Those constructing web application servers with Perl’s HTTP::Daemon module will encounter a 16,384 byte limit on the combined size of all HTTP request headers. This does not include POST-method form data, file uploads, etc., but it does include the URL. In practice this resulted in a 413 error when a URL was significantly longer than 8,000 characters. This limitation can be easily removed. Look for all occurrences of 16×1024 in Daemon.pm and replace them with a larger value. Of course, this does increase your exposure to denial of service attacks.
Recommendations
Extremely long URLs are usually a mistake. URLs over 2,000 characters will not work in the most popular web browser. Don’t use them if you intend your site to work for the majority of Internet users.When you wish to submit a form containing many fields, which would otherwise produce a very long URL, the standard solution is to use the POST method rather than the GET method:
<form action="myscript.php" method="POST">
...
</form>
The form fields are then transmitted as part of the HTTP transaction body, not as part of the URL, and are not subject to the URL length limit. Short-lived information should not be stored in URLs.As a rule of thumb, if a piece of information isn’t needed to regenerate the same page as a result of returning to a favorite or bookmark, then it doesn’t belong in the URL.
The Bookmark Problem
In very rare cases, it may be useful to keep a large amount of “state” information in a URL. For instance, users of a map-navigating website might wish to add the currently displayed map to their “bookmarks” or “favorites” list and return later. If you must do this and your URLs are approaching 2,000 characters in length, keep your representation of the information as compact as you can, squeezing out as much “air” as possible. If your field names take up too much space, use a fixed field order instead. Squeeze out any field that doesn’t really need to be bookmarked. And avoid large decimal numbers – use only as much accuracy as you must, and consider a base-64 representation using letters and digits (I didn’t say this was easy).In extreme cases, consider using the gzip algorithm to compress your pretty but excessively long URL. Then reencode that binary data in base64 using only characters that are legal in URLs. This can yield a 3-4x space gain, at the cost of some CPU time when you unzip the URL again on the next visit. Again, I never said it was easy!
An alternative is to store the state information in a file or a database. Then you can store only the identifier needed to look up that information again in the URL. The disadvantage here is that you will have many state files or database records. Some of which might be linked to on websites run by others. One solution to this problem is to delete the state files or database records for the URLs that have not been revisited after a certain amount of time.
“What happens if the URL is too long f
or the server?”What exactly happens if a browser that supports very long URLs (such as Firefox) submits a long URL to a web server that does not support very long URLs (such as a standard build of Apache)?
The answer: nothing dramatic. Apache responds with a “413 Entity Too Large” error, and the request fails.
This response is preferable to cutting the URL short, because the results of cutting the URL short are unpredictable. What would that mean to the web application? It varies. So it’s better for the request to fail.
In the bad old days, some web servers and web browsers failed to truncate or ignore long URLs, resulting in dangerous “buffer overflow” situations. These could be used to insert executable code where it didn’t belong… resulting in a security hole that could be exploited to do bad things.
These days, the major browsers and servers are secure against such obvious attacks – although more subtle security flaws are often discovered (and, usually, promptly fixed).
While it’s true that modern servers are themselves well-secured against long URLs, there are still badly written CGI programs out there. Those who write CGI programs in C and other low-level languages must take responsibility for paying close attention to potential buffer overflows. The CGIC library can help with this.
In any case, if you’re a web developer and you’re still asking this question, then you probably haven’t paid attention to my advice about how to avoid the problem completely.
How to optimize your PHP installation to handle large file uploads.
Though PHP presents a very versatile and user friendly interface for handling file uploads, the default installation is not geared for working with files in excess of 2 Mega Bytes. This article will help you configure your PHP engine for handling such large file transfers.
The php.ini File
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Special Note: You could be wasting bandwidth, If your file upload page is nothing more than an HTML form. Most browsers just ignore the MAX_FILE_SIZE hidden field and size limits are checked only after the data has been sent over the wire. Our applet saves your bandwidth by imposing client side restrictions. |
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All the configuration settings for your installation are contained in the php.ini file. Sometimes these setting might be overridden by directives in apache .htaccess files or even with in the scripts themselves. However you cannot over ride some of the settings that effect file uploads with .htaccess directives in this way. So let’s just concentrate on the ini file. If you do not have access to your PHP configuration file you can use the applet in resumable mode
You can call the phpinfo() function to find the location of your php.ini file, it will also tell you the current values for the following settings that we need to modify
- file_uploads
- upload_max_filesize
- max_input_time
- memory_limit
- max_execution_time
- post_max_size
The first one is fairly obvious if you set this off, uploading is disabled for your installation. We will cover the rest of the configuration settings in detail below.
upload_max_filesize and post_max_size
Files are usually POSTed to the webserver in a format known as ‘multipart/form-data’. The post_max_size sets the upper limit on the amount of data that a script can accept in this manner. Ideally this value should be larger than the value that you set for upload_max_filesize.
It’s important to realize that upload_max_filesize is the sum of the sizes of all the files that you are uploading. post_max_size is the upload_max_filesize plus the sum of the lengths of all the other fields in the form plus any mime headers that the encoder might include. Since these fields are typically small you can often approximate the upload max size to the post max size.
According to the PHP documentation you can set a MAX_UPLOAD_LIMIT in your HTML form to suggest a limit to the browser. Our understanding is that browsers totally ignore this directive and the only solution that can impose such a client side restriction is our own Rad Upload Applet
memory_limit
When the PHP engine is handling an incoming POST it needs to keep some of the incoming data in memory. This directive has any effect only if you have used the –enable-memory-limit option at configuration time. Setting too high a value can be very dangerous because if several uploads are being handled concurrently all available memory will be used up and other unrelated scripts that consume a lot of memory might effect the whole server as well.
max_execution_time and max_input_time
These settings define the maximum life time of the script and the time that the script should spend in accepting input. If several mega bytes of data are being transfered max_input_time should be reasonably high. You can override the setting in the ini file for max_input_time by calling the set_time_limit() function in your scripts.
Additonal Comments
Apache Settings
The apache webserver has a LimitRequestBody configuration directive that restricts the size of all POST data regardless of the web scripting language in use. Some RPM installations sets limit request body to 512Kb. You will need to change this to a larger value or remove the entry altogether.
Other Options
If you expect to handle a large number of concurrent file transfers on your website consider using a perl or java server side component. PHP happens to be our favourite web programming language as well but perl and Java are just slightly ahead when it comes to file upload.
Most installations of perl as an apache module can accept in excess of 32 megabytes out of the box. Compare this against the 2MB default for PHP. The downside is that perl coding takes just a bit more effort than PHP but it’s worth it. You can try our sample scripts to get started.
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