- To: linux clustering <linux-cluster@xxxxxxxxxx>
- Subject: Re: Throughput drops with VMware GFS2 cluster when using fence_scsi
- From: Greg Mortensen <thevision@xxxxxxxxx>
- Date: Fri, 2 Mar 2012 11:27:37 -0500
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<Responding to myself for benefit of the list>
This looks like it was caused by the device mapping defaulting to a
round-robin path selection policy. While I couldn't find any mention
of it in the RedHat cluster documentation, I did see some MSCS
postings[1] that said:
Round Robin can interfere with applications that use SCSI reservations
for sharing LUNs among VMs and thus is not supported with the use of
LUNs with MSCS.
so I changed the policy to "Most Recently Used" and was able to get
sustained writes of 40MB/s and sustained reads of 100MB/s down one
NIC.
Regards,
Greg
[1] http://en.community.dell.com/techcenter/storage/w/wiki/2671.aspx
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