VMware vSphere 5.5 is officially GA since few days. The whole vCloud suite starts to leverage Flash features (vFlash read cache) and upcoming VSAN. VSAN really is something that’s transforming the classic shared storage market and shared storage approach in design. VSAN is discussed briefly in the pdf Performance best practices for vSphere 5.5.
I’m planning to go test VSAN in my lab, so stay tuned.
Update: The lab is done – My VSAN journey – All Done! VSAN does not requires a 10Gb network speed for VSAN traffic, but it’s highly recommended by VMware.
Update 2: I flashed the Dell Perc H310 storage controller cards with an IT firmware. The queue depth went from 25 to 600 !! Low queue depth of storage adapter is principal bottlenecks during rebuilds and resynchronization operations in clusters running VSAN.
I’m not the first one to run Infiniband network in a lab, other bloggers did that too. You can check out @hypervisor_fr ( Hypervisor.fr) or @ErikBussink (Infiniband in the lab...). The the Infiniband cards are cheap through eBay, as well as old switches. I’ll see that in near future…
Now, back to the paper. Here is a quick quote concerning VSAN :
All VSAN writes go first to SSDs (solid-state disks) and VSAN read cache hits (which ideally make up a large proportion of the reads) come from SSD. Thus the performance of the SSDs is an important factor in the overall performance of VSAN.
This makes me think that if you’re going with cheap SSDs you might get a bad performance. This also might affect the design of VSAN installations. I’ll be definitely looking for an SSD which will be on the HCL .
The paper is very well written and it’s intended to be used by VMware architects and IT engineers designing and deploying vSphere.
Some additional links if you look for them and which might interests you:
- vSphere documentation: https://www.vmware.com/support/pubs
- Performance and other technical papers on the VMware Technical Papers page