RE: load level on linux mysql server out of control
I'ld suggest you guys round back to the version of MySQL that didn't have this problem, and try to figure out, possibly by giving MySQL AB access to the server(s), or installing a debuggable executable, what the problem is... Obviously, if two people are hit, the problem must be other than their env / code. Just my $0.02, Guus -Original Message- From: Henning Schroeder [mailto:[EMAIL PROTECTED]] Sent: Tuesday, September 11, 2001 2:07 AM To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: Re: load level on linux mysql server out of control At 01:46 11.09.01, you wrote: I'm having a lot of trouble tracing the origin of the problem -- sometimes it seems that accessing a particular large table is causing it, sometimes it seems that a combination of factors is causing it. Regardless, what I observe is that within 1 minute my load level climbs from between 2 and 4 to over 100, which I have never seen on any *nix system before. The RAM utilization is high, but not over 85%, and the CPU utilization fluctuates of course but stays below 40% user until whatever is causing my problems happens, and then it jumps to 100% and doesn't come down until I kill mysqld and let everything close. hi, same problem here. mysql 3.23.41, apache 1.3.20, php 4.0.6, kernel 2.2.19, debian system. 1GHz PIII 512MB. load 200. my fix for now till i have a better idea is to restrict the number of apache children to 60 which keeps the load 20. which is horrible nevertheless. and extremely slow for the users at times. the load normalizes (to something 4-ish, which is still pretty high for ~50q/s) again after ~15min. if you find out anything about that problem, PLEASE tell me. i´m searching for ~3 weeks and i´m not smarter in the least. and it sucks :-( at least i didn´t have that harddisk failures. yet. but then, it´s a colo machine so power should be fine. yes, dear mailing list, i know you told me my queries are, well, suboptimal. but i´m not quite sure about that. more tomorrow:-) greetings henning - 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
load level on linux mysql server out of control
I'm running mysql 3.23.41 on a PIII 800 Mhz machine with 512MB RAM, linux kernel 2.4.7, dedicated machine (ie, not running anything other than MySQL). I've been running mysql in a production environment for nearly 2 years, moderately hit (500,000 - 800,000 database connects per day) with no problems until very recently, and I'm trying to figure out what's going on. I just installed the 3.23.41 from source about 2 weeks ago, and fairly shortly thereafter I started seeing my load levels increase dramatically. This was on a faster machine with 1GB RAM...last week the hard drive developed bad sectors on a part of the disk where one of my larger and more frequently written tables lived, and that machine died a horrible death. So I chalked the load level increase up to bad hard drive, put the above-described machine in its place, and the load levels went thru the roof again. Ran isamchk and myisamchk -r on all problem tables. Verified the disk integrity...but yesterday the *new* disk failed at a block containing another big and heavily hit table started with the bad blocks...caught this one in time and moved the table someplace else. Two disks in one week makes me think of power fluctuations, and I'm wondering if this could be causing me to think the problem is MySQL and really it's a power spike during a table write?? And I wouldn't be seeing the same thing on the web server because it's not written to very often, unlike the mysql server... I'm having a lot of trouble tracing the origin of the problem -- sometimes it seems that accessing a particular large table is causing it, sometimes it seems that a combination of factors is causing it. Regardless, what I observe is that within 1 minute my load level climbs from between 2 and 4 to over 100, which I have never seen on any *nix system before. The RAM utilization is high, but not over 85%, and the CPU utilization fluctuates of course but stays below 40% user until whatever is causing my problems happens, and then it jumps to 100% and doesn't come down until I kill mysqld and let everything close. The database is being accessed almost entirely by PHP calls from php4.0.6 running with apache 1.3.20, using PHP's built in mysql functions. The web server lives on a different machine.Does anyone know of any problems with PHP and the newer versions of MySQL? What about large table handling on linux? I realise that if the tables aren't constructed properly they could cause problems, but these tables aren't *that* big...the data files are no more than 200Mb. And they seem to be using indexes correctly, and they've been running fine for nearly 2 years. These are mostly ISAM tables, if that makes a difference. This has been going on for the better part of a week now and I'm about out of guesses. We have combed our code for places where database connections aren't closed properly, we've split large tables off and checked indexing, we've even moved a high-volume read-only database onto the webserver itself to help lessen the load, and I don't know what else to do. If anyone can help, it will be greatly appreciated. TIA jenn - 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
Re: load level on linux mysql server out of control
At 01:46 11.09.01, you wrote: I'm having a lot of trouble tracing the origin of the problem -- sometimes it seems that accessing a particular large table is causing it, sometimes it seems that a combination of factors is causing it. Regardless, what I observe is that within 1 minute my load level climbs from between 2 and 4 to over 100, which I have never seen on any *nix system before. The RAM utilization is high, but not over 85%, and the CPU utilization fluctuates of course but stays below 40% user until whatever is causing my problems happens, and then it jumps to 100% and doesn't come down until I kill mysqld and let everything close. hi, same problem here. mysql 3.23.41, apache 1.3.20, php 4.0.6, kernel 2.2.19, debian system. 1GHz PIII 512MB. load 200. my fix for now till i have a better idea is to restrict the number of apache children to 60 which keeps the load 20. which is horrible nevertheless. and extremely slow for the users at times. the load normalizes (to something 4-ish, which is still pretty high for ~50q/s) again after ~15min. if you find out anything about that problem, PLEASE tell me. i´m searching for ~3 weeks and i´m not smarter in the least. and it sucks :-( at least i didn´t have that harddisk failures. yet. but then, it´s a colo machine so power should be fine. yes, dear mailing list, i know you told me my queries are, well, suboptimal. but i´m not quite sure about that. more tomorrow:-) greetings henning - 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
