On Aug 27, 2010, at 2:32 PM, Mark wrote: > Saddly most of those options will not work, since we are using a SUN Unified > Storage 7210, the only option is to buy the SUN SSD's for it, which is about > $15k USD for a pair. We also don't have the ability to shut off ZIL or any > of the other options that one might have under OpenSolaris itself :( > > It sounds like I do want to change to a RAID10 mirror instead of RAIDz. It > sounds like enabling write-cash without the ZIL in place might work but would > lead to corruption should something crash. > > So the question is with a proper ZIL SSD from SUN, and a RAID10... would I be > able to support all the VM's or would it still be pushing the limits a 44 > disk pool?
We run roughly that number of VMs on ESXi 4 using a 7410 and a 7310 via NFS. The 7410 and 7310 have fewer disks (24), but they are arranged in a mirror configuration. Each has both readzilla and logzilla SSDs. Our VMs are similarly lightly loaded (much like yours...mix of Windows and Ubuntu, about 25% run a DB server with very little load). We use compression but not deduplication. It has worked extremely well for us. No complaints on speed, very stable. From what I have read on this list iscsi will not be a huge speed improvement for you (though we haven't tried it), and you give up a lot of management flexibility vs. NFS. I would say that the 7210 should be able to support your needs if you put SSDs in based on our experience (and the 7210 has more disks than our 7310 or 7410). Of course switching to a mirror pool requires destroying your current configuration, so it isn't easy. You might also need to remove some HDDs to make room for the SSDs. As far as analytics, the ARC stats (hit/miss) are available which will give you some indication of whether an L2ARC will help. On the SLOG, look at latency by file and operation for a VM that is having performance issues...is it showing high latency on NFS writes? Good luck, Ware _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
