Date: Sat, 13 Jan 2007 19:13:12 +1300 From: Mark Kirkwood <markir@paradise.net.nz> To: Michel Santos <michel@lucenet.com.br> Cc: freebsd-performance@freebsd.org Subject: Re: diskio low read performance Message-ID: <45A87878.1050505@paradise.net.nz> In-Reply-To: <64656.200.152.83.36.1168651673.squirrel@webmail.matik.com.br> References: <64656.200.152.83.36.1168651673.squirrel@webmail.matik.com.br>
next in thread | previous in thread | raw e-mail | index | archive | help
Michel Santos wrote: > I hope somebody can help me. I upgraded recently my cache server (squid) > 4.11 to 6.2 > > I notice that my disk read performance seems to be low. I observe it by > reading diskio from net-snmp. I started to check this because my old > server gave much better results from cache. > > I see read access as 1/4 - 1/6 of write access. My cache_dirs are full and > no swap in use. IOLA is not over 25-30 in peaks > > is there some special configuration to get better read performance on 6.2? > My disks are UW320 10k on Adaptec 29320 and the same as on the 4.11 > server. I really dont care about write speed so much so if there are > parameters to configure I apreciate to hear about. > > I checked the following with 1 and 0 but it does not make any difference > at all > > vfs.write_behind > vfs.vmiodirenable > > I get an average of 6-8Mb/s through this server and 3-4 of it is http > traffic. I see the object are going into the cache but for some reason it > seems they can not be read in time. > > I tried different newfs -b and -f and actually 1024/4096 seems to be best. > I do not cache large files on this machine. > > > Is there something I sgould try? > Note sure this will help you, as your files are all small, but try increasing vfs.read_max (say 16 or 32). Cheers Mark
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?45A87878.1050505>