Re: diskio low read performance


Kris Kennaway disse na ultima mensagem:
On Sat, Jan 13, 2007 at 04:58:06PM -0200, Michel Santos wrote:

I have two server, the main server is a Supermicro Dualcore Dual Opteron
and the backup is a Athlon64 X2, both with 4GB

The disks are the same, only the onboard SCSI is Adaptec and the other
is
LSI. Funny is that I have no difference regarding the disk read
performance wether I use the Opteron machine or the other

dmesg Opteron
http://suporte.lucenet.com.br/ms/dmesg.sm

dmesg X2
http://suporte.lucenet.com.br/ms/dmesg.x2

kernel config
http://suporte.lucenet.com.br/ms/kernel62

options SCHED_ULE # ULE scheduler

From the NOTES file from where you copied this:

# SCHED_ULE is a new scheduler that has been designed for SMP and has some
# advantages for UP as well. It is intended to replace the 4BSD scheduler
# over time. NOTE: SCHED_ULE is currently considered experimental and is
# not recommended for production use at this time.

When investigating problems with your system, your very first step
should be to revert the use of code marked "experimental" and "not
recommended for production use" ;-)


I am running both (on at a time of course :) ), now for six month or so,
ULE is giving me better overall performance, either with or w/o polling. I
mean network performance. I have net.isr.enable=1 and
net.inet.ip.fastforwarding=1,
this way I do get the same network performance I had on the 4.11. I mean I
have no problem here.

But also I checked the ULE/BSD against my particular problem and there is
no difference at all. I get no acceptable disk read performance when
comparing what I had with 4.11, wether with ULE or with 4BSD


Michel





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




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