Re: [PHP] Persistent Database Connections
Michael Phillipson wrote: [Please note that even though I cite Interbase in my example, I believe my question can be generalized to all databases that allow persistent connections] I recently installed a trial version of Interbase on a development server firebird-loon have you tried the free trial version of Firebird, with the added bonus that its not a trial... and has a cooler name :-/ /firebird-loon that includes a nifty tool that allows me to monitor, among other things, ... -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Persistent Database Connections
Thanks, Philip (and Richard also), for offering your impressions. Per Philip's suggestion, I ran ab (Apache Benchmark) to stress test the page that loads my persistent connection. Depending on the parameters I set for ab, I was able to increase the number of connections from my initial 9 to anywhere between 15 and 25. This number varied from one test to another - even if I left the ab parameters the same. I probably could have boosted the total connections even further by raising the number of connections/requests initiated by ab. So, while I still don't have a rock-solid way to predict just how many connections will be opened for a given number of users, at least I'm not stuck at 9 :-) I guess it took using an automated approach to simulating server load (e.g., ab) to force Apache to open additional connections to the database. Interestingly, I also observed during my testing that some connections opened by Apache were subsequently closed. So, this seems to answer my other question re. whether persistent connections stay open forever. I guess they don't. What seems clear is that Apache decides when to terminate active connections, not the database. Thanks again. Mike Philip Hallstrom [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] What I am baffled by is the fact that the total nunber of connections between the web server and my database seems to max out at 9. Why 9? Not that I have a problem with this number. I just want to understand how this limit was reached so that I might predict how the application will perform in a production capacity. I can't think of a reason it would max out at 9 other than perhaps you really don't have more than 9 connections open. My understanding is that Apache will open a connection per child, per database connection where a connection is made up of the host, user, and database. How many apache processes are running when you take this measurement? There's no gaurantee that each of them will have hit your web app and start up there own connection. You might use something like ab (apache benchmark) to hit a page that initiates a persistent connection to see what happens as the number of apache processes grows. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Persistent Database Connections
I recently installed a trial version of Interbase on a development server that includes a nifty tool that allows me to monitor, among other things, the number of active connections to my server. After playing with this feature briefly, I noticed that SEVERAL connections are opened between my web server and the database. At first, I thought this was a little weird because I use the ibase_pconnect() function to establish communication with my database, and I expected to see only 1 connection. However, after doing some reading, I discovered that this behavior is probably by design - the result of Apache spawning several child processes, each one establishing its own persistent connection(s) to the database. What I am baffled by is the fact that the total nunber of connections between the web server and my database seems to max out at 9. Why 9? Not that I have a problem with this number. I just want to understand how this limit was reached so that I might predict how the application will perform in a production capacity. I can't think of a reason it would max out at 9 other than perhaps you really don't have more than 9 connections open. My understanding is that Apache will open a connection per child, per database connection where a connection is made up of the host, user, and database. How many apache processes are running when you take this measurement? There's no gaurantee that each of them will have hit your web app and start up there own connection. You might use something like ab (apache benchmark) to hit a page that initiates a persistent connection to see what happens as the number of apache processes grows. I have checked my Apache config (httpd.conf) file, and as far as I can tell, the maximum number of child processes is set to 20. So again I ask: why does the number of connections max out at 9? Shouldn't they max out at 20 or 21 (1 parent + 20 children)? Not necessarily (see above). It could very well be that for 20 children you could have *more* than that number of connections if your web pages connect to multiple databases... And finally, I have noticed that the connections, once established, NEVER expire. I realize that this is sort of the point with persistent connections, but I was curious whether persistent connections are ever terminated or recycled. I don't think so. I suppose the database could kill lingering connections... I don't know about that. What I've done in the past is to set the number of requests each apache child is allowed to serve to some number that will be reached on some reasonable frequency. Then it closes that child which closes the connections... Any explanations/impressions would be appreciated. Mike FYI... My php.ini file is set to allow unlimited connections/unlimited persistent connections. Also, the trial license of the database I am testing claims to be limited to 1 client, and the only client accessing the database is my web app. Just thought I'd mention that as I don't think the number of connections has any direct correlation to the client license. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Persistent Database Connections
On Mon, April 25, 2005 1:40 pm, Michael Phillipson said: What I am baffled by is the fact that the total nunber of connections between the web server and my database seems to max out at 9. Why 9? Either you never had more than 9 users at one time during your test, so only 9 Apache children actually had to do any work, and the rest just laid around doing nothing, or... You may have configured Interbase (no idea how) to only allow 9 connections, or The trial version of Interbase may limit you to 9 (or 10) connections. If you also had, say, some kind of shell Interbase monitor program going, or some kind of other application with a connection, that would have been your 10th connection. If this were MySQL, I'd tell you to look at your /etc/my.cnf file, or to create one, and to make sure your limit on the number of connections is *HIGHER* than the number of Children you allow in httpd.conf Othewise, sooner or later, your server gets busy, and BAM! you've hit a wal where Apache *wants* a MySQL connection, but MySQL won't give it one, and your user gets some nasty error message about it, or, if you are re-directing the errors, the page just plain doesn't work the way they want, or... Exactly what happens depends on your error settings and error handling, and how good your code is at detecting error conditions. You want the MySQL limit *HIGHER* than the Children, so that if all hell breaks loose, *YOU* can use the mysql monitor from the shell command line to log in and do admin tasks, yay even unto mysqladmin -u root -p stop You don't want to get caught where your site is *SO* busy you can't even get that to work. :-^ Interbase presumably has similar features, but I cannot say for certain. -- Like Music? http://l-i-e.com/artists.htm -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP] Persistent database connections in PHP
do people even look at the manual? or search the php.net website? http://au2.php.net/manual/en/ref.mysql.php Runtime Configuration The behaviour of these functions is affected by settings in php.ini. Here's a short explanation of the configuration directives. mysql.allow_persistent boolean Whether to allow persistent connections to MySQL. so if you installed PHP without modifying the ini file, all your connections should be persistent -Mensaje original- De: Shivanischal [mailto:[EMAIL PROTECTED] Enviado el: Viernes, 05 de Septiembre de 2003 01:05 a.m. Para: [EMAIL PROTECTED] Asunto: [PHP] Persistent database connections in PHP Hi friends, I wanted help on how to achieve persistent database connections in PHP. The database i use is MySQL. I would be grateful if u could also guide me to resources that tell me how to do it. Thanks, -shiva -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php * This e-mail, including any attachments to it, may contain confidential and/or personal information. If you have received this e-mail in error, you must not copy, distribute, or disclose it, use or take any action based on the information contained within it. Please notify the sender immediately by return e-mail of the error and then delete the original e-mail. The information contained within this e-mail may be solely the opinion of the sender and may not necessarily reflect the position, beliefs or opinions of Salmat on any issue. This email has been swept for the presence of computer viruses known to Salmat's anti-virus systems. For more information, visit our website at www.salmat.com.au. * -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP] Persistent database connections in PHP
ooppss forgot this as well... http://au2.php.net/mysql_pconnect -Original Message- From: Cody Phanekham Sent: Friday, 5 September 2003 16:06 To: [EMAIL PROTECTED] Subject: RE: [PHP] Persistent database connections in PHP do people even look at the manual? or search the php.net website? http://au2.php.net/manual/en/ref.mysql.php Runtime Configuration The behaviour of these functions is affected by settings in php.ini. Here's a short explanation of the configuration directives. mysql.allow_persistent boolean Whether to allow persistent connections to MySQL. so if you installed PHP without modifying the ini file, all your connections should be persistent -Mensaje original- De: Shivanischal [mailto:[EMAIL PROTECTED] Enviado el: Viernes, 05 de Septiembre de 2003 01:05 a.m. Para: [EMAIL PROTECTED] Asunto: [PHP] Persistent database connections in PHP Hi friends, I wanted help on how to achieve persistent database connections in PHP. The database i use is MySQL. I would be grateful if u could also guide me to resources that tell me how to do it. Thanks, -shiva -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php ** *** This e-mail, including any attachments to it, may contain confidential and/or personal information. If you have received this e-mail in error, you must not copy, distribute, or disclose it, use or take any action based on the information contained within it. Please notify the sender immediately by return e-mail of the error and then delete the original e-mail. The information contained within this e-mail may be solely the opinion of the sender and may not necessarily reflect the position, beliefs or opinions of Salmat on any issue. This email has been swept for the presence of computer viruses known to Salmat's anti-virus systems. For more information, visit our website at www.salmat.com.au. ** *** -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Persistent database connections in PHP
Just use the same header. and in the next page use body onload=window.open(yourpage) ... Murugesan - Original Message - From: Cesar Aracena [EMAIL PROTECTED] To: 'Shivanischal' [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Sent: Friday, September 05, 2003 11:27 AM Subject: RE: [PHP] Persistent database connections in PHP I haven't heard of persistent connections with MySQL before, and I think is because PHP can't handle it. PHP will connect to the DB every time it has to. Are you really that annoyed for that 0.0003 second that it probably takes your pages to connect to the DB? What I do to manage just ONE connection request per visitor, is request a mainfile.php which also declares a function that connects to the DB. After that is prepared to handle all the queries you want. HTH, Cesar Aracena www.icaam.com.ar -Mensaje original- De: Shivanischal [mailto:[EMAIL PROTECTED] Enviado el: Viernes, 05 de Septiembre de 2003 01:05 a.m. Para: [EMAIL PROTECTED] Asunto: [PHP] Persistent database connections in PHP Hi friends, I wanted help on how to achieve persistent database connections in PHP. The database i use is MySQL. I would be grateful if u could also guide me to resources that tell me how to do it. Thanks, -shiva -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] Persistent database connections in PHP
On Fri, 5 Sep 2003, Shivanischal wrote: I wanted help on how to achieve persistent database connections in PHP. The database i use is MySQL. I would be grateful if u could also guide me to resources that tell me how to do it. http://www.php.net/manual/en/function.mysql-pconnect.php -- Mika Tuupola http://www.appelsiini.net/~tuupola/ -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
RE: [PHP] Persistent database connections in PHP
I haven't heard of persistent connections with MySQL before, and I think is because PHP can't handle it. PHP will connect to the DB every time it has to. Are you really that annoyed for that 0.0003 second that it probably takes your pages to connect to the DB? What I do to manage just ONE connection request per visitor, is request a mainfile.php which also declares a function that connects to the DB. After that is prepared to handle all the queries you want. HTH, Cesar Aracena www.icaam.com.ar -Mensaje original- De: Shivanischal [mailto:[EMAIL PROTECTED] Enviado el: Viernes, 05 de Septiembre de 2003 01:05 a.m. Para: [EMAIL PROTECTED] Asunto: [PHP] Persistent database connections in PHP Hi friends, I wanted help on how to achieve persistent database connections in PHP. The database i use is MySQL. I would be grateful if u could also guide me to resources that tell me how to do it. Thanks, -shiva -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
