On Oct 4, 2012, at 1:33 PM, "Schweiss, Chip" <c...@innovates.com> wrote:
> Again thanks for the input and clarifications.
> I would like to clarify the numbers I was talking about with ZiL performance
> specs I was seeing talked about on other forums. Right now I'm getting
> streaming performance of sync writes at about 1 Gbit/S. My target is closer
> to 10Gbit/S. If I get to build it this system, it will house a decent size
> VMware NFS storage w/ 200+ VMs, which will be dual connected via 10Gbe.
> This is all medical imaging research. We move data around by the TB and fast
> streaming is imperative.
> On the system I've been testing with is 10Gbe connected and I have about 50
> VMs running very happily, and haven't yet found my random I/O limit. However
> every time, I storage vMotion a handful of additional VMs, the ZIL seems to
> max out it's writing speed to the SSDs and random I/O also suffers. With
> out the SSD ZIL, random I/O is very poor. I will be doing some testing with
> sync=off, tomorrow and see how things perform.
> If anyone can testify to a ZIL device(s) that can keep up with 10GBe or more
> streaming synchronous writes please let me know.
Quick datapoint, with qty 3 ZeusRAMs as striped slog, we could push 1.3
storage vmotion on a relatively modest system. To sustain that sort of thing
full system-level tuning and proper systems engineering design. Fortunately,
tend to not do storage vmotion on a continuous basis.
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