<div dir="ltr"><br><div class="gmail_extra">Just wanted to pick up on the EC for vm storage domains option..</div><div class="gmail_extra"><br></div><div class="gmail_extra"><br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class=""><br>
> * Erasure coded volumes with sharding - seen as a good fit for VM disk<br>
> storage<br>
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</span>I am working on this with a customer, we have been able to do 400-500 MB / sec writes! Normally things max out at ~150-250. The trick is to use multiple files, create the lvm stack and use native LVM striping. We have found that 4-6 files seems to give the best perf on our setup. I don't think we are using sharding on the EC vols, just multiple files and LVM striping. Sharding may be able to avoid the LVM striping, but I bet dollars to doughnuts you won't see this level of perf :) I am working on a blog post for RHHI and RHEV + RHS performance where I am able to in some cases get 2x+ the performance out of VMs / VM storage. I'd be happy to share my data / findings.<br>
<span class=""><br></span></blockquote><div><br></div><div>The main reason IIRC for sharding was to break down the vdisk image file into smaller chunks to improve self heal efficiency. With EC the vdisk image is already split, so do we really need sharding as well - especially given Ben's findings?</div><div><br></div><div><br></div><div><br></div></div></div></div>