Original URL: http://www.theregister.co.uk/2012/03/20/avere_vs_netapp_boot_storm/

Avere attacks filer VDI boot slowdown

Boot storm delay goes away

By Chris Mellor

Posted in Storage, 20th March 2012 18:01 GMT

NAS accelerator supplier Avere can make NetApp VDI boot storm delays go away, and it has the numbers to prove it.

By placing a multi-tiered, solid state and hard drive caching Avere FXT filer accelerator in front of a NetApp filer, VDI boot storm files are transferred to the FXT and served up to booting devices faster and at a more consistent speed than from the back end filer.

Avere said testing of up to 145 Virtual Machines (VMs) scattered across multiple ESXi servers each using a single datastore on an entry-level Avere FXT-2550 maintained consistently fast sub 90-second boot times."

An Avere spokesperson said: "Using the Avere Dashboard Analytics, we were able to determine that booting Windows 7 64-bit, with 16GB VMDK and 2GB of memory, requires an approximate 340MB of hot data."

If you put that hot data in a solid state cache then it will be served up far faster than from spinning disk.

Avere found that a NetApp FAS2050 array would start to exhibit VM boot times 113 per cent longer with as few as 16 virtual machines (VMs) booting simultaneously. An Avere FXT2550 front-ending the FAS250 was able to boot up to 115 VMs scattered across multiple ESXi servers with a fairly consistent boot time.

The chart below shows a before and after comparison.

Avere versus raw NetApp with VDI boot storms

Boot storm relief from Avere FXT2550 accelerating NetApp arrays

The FAS2050 configuration was a single-head filer with 12 x 500GB SATA 7200rpm disks. The FAS3240 was also single-headed with 24 x 2TB SATA 7200rpm disks.

An Avere spokesperson said: "Neither of these filers were populated with FlashCache cards.

"The FAS2000 series does not have hardware that is compatible with FlashCache. So anyone out there running a FAS2000 series has no option to add a FlashCache card.[The] only option is to upgrade the filer head and buy a FlashCache card. ... we can optimise a FAS2000 series filer that would otherwise have to be forklift-upgraded."

He added this little PR nugget: "A school district in Massachusetts gained instant relief from the storage performance issues plaguing their NetApp FAS2000 due to logon/logoff storms." ®