Posted by Julian Sutter on March 21, 2014 at 17:14:32:
In Reply to: Re: COMET 32 AND XAP posted by jim guerber on March 21, 2014 at 10:59:52:
Hi Steve! I bet you are looking forward to spring, it was pretty brutal out there when I was out last.
We've found that Comet is particularly sensitive to storage latency, and in a virtualized environment this is usually the defining performance factor. Because our we do VDI, we built our entire system around minimizing storage latency (dual 10g fabrics, storage tiering, etc), and even still in test4 with the parameters you mentioned we can only manage approx 4 seconds. We're hoping to add an SSD tier later this year, which I think should cut this by an order of magnitude. SSD is the best thing to happen to comet since... Win32. ;)
KVM and Server 2k12 could both be contributing to the speed issue too, but I'd start with storage. Can you describe the disk subsystem with more detail on the host you are running this virtual server on?
Also, I've found that KVM is pretty sensitive when it comes to 32 bit applications. VMware seems to be more predictable, but it's expensive. With Server 2k12, are you using NTFS deduplication or any of the more advanced NTFS features?
Finally, I'd be happy to spin you up a test server on our platform so you have a benchmark to test against.
Hope you are doing well, feel free to give me a ring!
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