Hi all! I recently bought a dedicated server for our forum. Problem we're facing is a high load and slow performance of the forum. As a test I migrated the server to a less powerful server were the load was way lower, and pages ran faster. 23:25:16 up 25 days, 7:29, 2 users, load average: 5.27, 4.34, 4.63 server specs/details: Code: Linux removed 2.6.18-4-686 #1 SMP Mon Mar 26 17:17:36 UTC 2007 i686 GNU/Linux Version Code: removed:~# cat /etc/debian_version 3.1 CPU Code: removed:~# cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 15 model : 2 model name : Intel(R) Pentium(R) 4 CPU 2.66GHz stepping : 9 cpu MHz : 2665.609 cache size : 512 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe up cid xtpr bogomips : 5335.15 Memory Code: removed:~# cat /proc/meminfo MemTotal: 2068896 kB MemFree: 301168 kB Buffers: 170792 kB Cached: 803312 kB SwapCached: 0 kB Active: 1313544 kB Inactive: 361000 kB HighTotal: 1171392 kB HighFree: 25296 kB LowTotal: 897504 kB LowFree: 275872 kB SwapTotal: 2706912 kB SwapFree: 2706876 kB Dirty: 11540 kB Writeback: 0 kB AnonPages: 575604 kB Mapped: 19936 kB Slab: 83156 kB PageTables: 3332 kB NFS_Unstable: 0 kB Bounce: 0 kB CommitLimit: 3741360 kB Committed_AS: 929176 kB VmallocTotal: 114680 kB VmallocUsed: 4084 kB VmallocChunk: 110520 kB MySQL version: Code: MySQL on localhost (5.0.32-Debian_7etch1-log) removed:~# mysql -V mysql Ver 14.12 Distrib 5.0.32, for pc-linux-gnu (i486) using readline 5.2 PHP version Code: PHP Version 4.4.4-8+etch1 Apache version Code: removed:~# apache2 -v Server version: Apache/2.2.3 Server built: Mar 27 2007 15:06:55 The server it used to run on had MySQL 4, so did the other server I tried the forum on. We have an avarage of +90 users online. MySQl seems to be the trouble maker as far as I can tell, when I stop MySQL the load goes down very fast. I did ran slow queries and stuff, and disabled plugins the forum was using.. but they ran fine on the other hardware so im not too sure about this. I suspect the problem has to do with my MySQL version, or some sort of conflict with it. Is there any way to downgrade MySQL, and is it wise to do this? Any information would be much appreciated! Thanks in advance
You can try to optimize MySQL by tuning my.cnf. This link might help you: http://dev.mysql.com/doc/refman/5.0/en/optimizing-the-server.html Also, you should install munin to get graphs and see what the real bottleneck is. Do you have a PHP cache (something like eaccelerator) installed?
MySQL is tuned, tried different settings.. and the one that works ok on other servers. As for caching I use memcached. I have not tried munin yet, will install it today. As for the downgrade, is it possible? Also I installed mysql-4 but the version says 5. When I try to apt-get mysql 4 it says its already installed, yet the version still says 5. bit weird imho
Hi sorry for the late reply been away for a few days. This happened when I first installed this machine, and mysql has been restarted many times since Code: removed:/var/lib/mysql# dpkg -l|grep mysql ii courier-authlib-mysql 0.58-4 MySQL support for the Courier authentication ii libdbd-mysql-perl 3.0008-1 A Perl5 database interface to the MySQL data ii libmysql++-dev 2.0.7-3 mysql C++ library bindings (development) ii libmysql++2c2a 2.0.7-3 mysql C++ library bindings (runtime) ii libmysqlclient15-dev 5.0.32-7etch1 mysql database development files ii libmysqlclient15off 5.0.32-7etch1 mysql database client library ii mysql-client 5.0.32-7etch1 mysql database client (meta package dependin ii mysql-client-5.0 5.0.32-7etch1 mysql database client binaries ii mysql-common 5.0.32-7etch1 mysql database common files (e.g. /etc/mysql ii mysql-server 5.0.32-7etch1 mysql database server (meta package dependin ii mysql-server-4.1 5.0.32-7etch1 mysql database server (transitional package) ii mysql-server-5.0 5.0.32-7etch1 mysql database server binaries ii php4-mysql 4.4.4-8+etch1 MySQL module for php4 ii postfix-mysql 2.3.8-2+b1 MYSQL map support for Postfix Code: removed:~# apt-get install php4-mysql Reading Package Lists... Done Building Dependency Tree... Done php4-mysql is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 163 not upgraded. Code: removed:~# apt-get install mysql-server-4.1 Reading Package Lists... Done Building Dependency Tree... Done mysql-server-4.1 is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 163 not upgraded. Code: removed:~# apt-get install mysql-client-4.1 Reading Package Lists... Done Building Dependency Tree... Done Note, selecting mysql-client-5.0 instead of mysql-client-4.1 mysql-client-5.0 is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 163 not upgraded. would this last part be a problem? How easy would it be to revert this back to mysql-client-4.1, and how? Would the db be still intact, or can I copy a mysql directory structure and then place it back? thanks in advance
You can try this: Back up the /var/lib/mysql directory, then run Code: apt-get remove mysql-server-5.0 mysql-client-5.0 apt-get install mysql-server-4.1 mysql-client-4.1 and then replace the new /var/lib/mysql directory with your backup.
removed:~# cat /etc/apt/sources.list #deb file:///cdrom/ sarge main deb http://ftp.nl.debian.org/debian/ stable main deb-src http://ftp.nl.debian.org/debian/ stable main deb http://security.debian.org/ stable/updates main blob:~#
Please change it to Code: #deb file:///cdrom/ sarge main deb http://ftp.nl.debian.org/debian/ sarge main deb-src http://ftp.nl.debian.org/debian/ sarge main deb http://security.debian.org/ sarge/updates main , run Code: apt-get update , and try again.
