after reading this email, i switched from aufs to diskd to see performance of them under high load .. with aufs, squid never used more than 10% of cpu and response time is very low (5ms to 150ms).. with diskd cpu usage goes to 50% +- and median response time up to 900ms !! i´m running CentOS 5.0 with kernel 2.6.22, quad opteron 64 bits with 4gb ram and hd are SAS 15.000 rpm attached graphic of cpu usage !! On 8/10/07, Michel Santos <michel@xxxxxxxxxxxxxx> wrote: > > Henrik Nordstrom disse na ultima mensagem: > > On fre, 2007-08-10 at 06:50 -0300, Michel Santos wrote: > > >> what is what you agree to be broken beyond the shutdown issue? > > > > Bug #761 unstable under high load when using diskd cache_dir > > > > diskd falls over under load due to internal design problems in how it > > maintains callback queues. Duane fixed most of it quite recently so it's > > no longer near as bad as it has been, but there is still stuff to do. > > The problems was first reported 5 years ago. > > > > indeed the cpu load went extremly down after this changes, I won on much > machines more then 30-40%, or better 70/80% cpu load felt down to 30-40% > overall. That was very good > > but I could get araound of it before and still do using at least 2 or > better 4 or more diskd processes > > >> ok you mean threads instead of pthreads right? > > > > I don't know the FreeBSD thread packages very well to call them by name. > > I only know there is two posix threads implementations. One userspace > > which is what has been around for a long time and can not support aufs > > with any reasonable performance, and a new one in more current releases > > using kernel threads which is quite capable of supporting aufs. > > it it pthread versus thr (kernel threads) and who is interested, it's easy > to do on 6.2 by creating /etc/libmap.conf or adding if exist, no further > compile thing is necessary > > [/usr/local/squid/sbin/squid] > libpthread.so.2 libthr.so.2 > libpthread.so libthr.so > > > > Michel > ... > > > > > **************************************************** > Datacenter Matik http://datacenter.matik.com.br > E-Mail e Data Hosting Service para Profissionais. > **************************************************** > > -- Sds. Alexandre J. Correa Onda Internet / OPinguim.net http://www.ondainternet.com.br http://www.opinguim.net
Attachment:
cpu.day.png
Description: PNG image
