On Jun 18, 2012, at 7:02 AM, "George Shuklin" <george.shuk...@gmail.com> wrote:
> Good day. > > I'm trying to rid of bottleneck in SAN environment. After some tests > I've came to conclusion that bottleneck is in open-iscsi or IET. > > Here simple test to check it: > > 1) Setup relatively fast array of disks (in my case it is about 20 SATA > drives in raid10) > 2) set up iet in blockio mode. > 3) discover/login on it locally (no network, no switches, just lo0) > 4) run fio with following config: > [test] > blocksize=4k > filename=/dev/sdal #iscsi disk > rw=randwrite > direct=1 > buffered=0 > ioengine=libaio > iodepth=32 > > What I see: > > sdal (open-iscsi disk) utilization is 100%, all other disks are below > 50% (about 35-45%) > > Changing filename from iscsi disk to raid disk (which is exported by > iet) raise performance (in my case with 20 SATA disks from 4.5k IOPS to > 5.4k IOPS). I don't quite understand this, do you mean the performance of going direct to the native raid was 5400 IOPS? You could try disabling rx/tx checksums on the loopback if enabled. -Ross ______________________________________________________________________ This e-mail, and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail, you are hereby notified that any dissemination, distribution or copying of this e-mail, and any attachments thereto, is strictly prohibited. If you have received this e-mail in error, please immediately notify the sender and permanently delete the original and any copy or printout thereof. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to open-iscsi@googlegroups.com. To unsubscribe from this group, send email to open-iscsi+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
