diskio low read performance


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?

Michel







computador é como nem cavalo e mulher
mais que montam neles, pior que ficam ...




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  • Re: diskio low read performance
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