Rahul Nabar wrote:
On Fri, Sep 25, 2009 at 2:38 PM, Rahul Nabar <rpna...@gmail.com> wrote:
We use this to model bonnie++ and other types of workloads. It provides a
great deal of useful information.
More details from the fio benchmark.....
##################################################################################################
fio: terminating on signal 2
random: (groupid=0, jobs=16): err= 0: pid=26509
read : io=12,391MiB, bw=3,732KiB/s, iops=466, runt=3399938msec
clat (msec): min=3, max=1,122, avg=23.06, stdev= 4.38
bw (KiB/s) : min= 7, max= 621, per=9.34%, avg=348.67, stdev=29.11
cpu : usr=0.04%, sys=0.17%, ctx=3736755, majf=0, minf=33036
IO depths : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued r/w: total=1586090/0, short=0/0
lat (msec): 4=0.01%, 10=0.38%, 20=17.11%, 50=69.74%, 100=12.01%
lat (msec): 250=0.73%, 500=0.02%, 750=0.01%, 1000=0.01%, 2000=0.01%
Looks like your IOP latency is around 50ms. If you think about this, it
seems a little high, even for a RAID5. I'll do some measurements here
on our big units and we can compare.
466 IOP is ok ... basically 4 drives will give you this (5 RAID5 drives
-> 4 drives of data). If you are IOP bound, you can do better, if this
matters.
--
Joseph Landman, Ph.D
Founder and CEO
Scalable Informatics Inc.
email: land...@scalableinformatics.com
web : http://scalableinformatics.com
http://scalableinformatics.com/jackrabbit
phone: +1 734 786 8423 x121
fax : +1 866 888 3112
cell : +1 734 612 4615
_______________________________________________
Beowulf mailing list, Beowulf@beowulf.org sponsored by Penguin Computing
To change your subscription (digest mode or unsubscribe) visit
http://www.beowulf.org/mailman/listinfo/beowulf
