The first thing that comes to mind is that you're running the databases on different hardware and operating systems. I know the Linux kernel had some SMP performance issues not too long ago, prompting IBM to rewrite portions of the kernel and improving performance by (I think) 16-20%. Also, you're only using one processor at a time if your test isn't multithreaded.
The general overhead of SMP combined with Linux kernel issues may be where the difference is. I would format a new hard drive with Linux (non-SMP), temporarily install it in the W2K box and see what numbers you get. Bret -----Original Message----- From: Ioakim Spyros [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 17, 2002 12:53 PM To: [EMAIL PROTECTED] Subject: FW: Optimization Hello all, I'm having real trouble trying to optimize MySQL cause I can't believe that MSSQL is faster. My configurations are as follows: MSSQL 2000 on W2K server. PIII 733 - 512 MB memory. MySQL-3.23.47-1 on Redhat 7.2. Dual PIII 1000 - 1.128 GB memory I have a PHP script that runs on a Redhat 7.1 - PIII 500 640 MB memory. The php script takes a username from a mysql table and runs a query for each of the usernames on another table. The test is that I have 2 different versions of the script that do the exactly same thing but one queries the MSSQL server and the other the MySQL. The MSSQL version takes 28 secs while the MySQL takes 34 secs. As you can see the MSSQL is much more slower with less RAM. I said what the heck I will use the my-huge.cnf to see if it makes any difference. Unfortunately nothing changed and then I started panicking.. It can't be true! I noticed that MSSQL caches the queries while MySQL doesn't. In my script I might have this: select emails from dbo_Company where username='1111'; come up 5 or even 10 times. If I run it on mysql It takes always 0.26 secs while it appears the MSSQL caches the result and doesn't take any time at all. If I get the same query in the script 10 times I'm losing immediately 2.34 secs with MySQL. Is there a way to get the same behavior in MySQL.. Regards, Spyros --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
