VMware Virtual SAN 6.0 benchmark

Last week I was going through ‘What’s New: VMware Virtual SAN 6.0‘, it seems like VSAN 6.0 is bigger, better and faster. The latest installment of VMware’s distributed storage platform provides a significant IOPS boost, up to twice the performance in hybrid mode. The new VirstoFS on-disk format is capable of high performance snapshots and clones. Time to put it to the test.

 

Disclaimer: this benchmark has been performed on a home lab setup, components used are not listed in the VSAN HCL. My goal is to confirm an overall IOPS and snapshot performance increase by comparing VSAN 5.5 with 6.0. I did so by running a synthetic IOmeter workload.

VMware has a really nice blogpost on more advanced VSAN performance testing utilizing IOmeter.

 

Hardware

My lab consists of 3 Shuttle SZ87R6 nodes, connected by a Cisco SG300.

 Chipset  Z87
 Processor  Intel Core i5-4590S
 Memory  32 GB
 NIC 1  1 GE (management)
 NIC 2  1 GE (VSAN)
 HDD 1  Samsung 840 Evo (120GB)
 HDD 2  HGST Travelstar 7K1000 (1TB)

 
 

ESXi/VSAN versions

  • ESXi 5.5 Update 2 (build 2068190)
  • ESXi 6.0 (build 2494585)

vSphere 6: mClock scheduler & reservations

“Storage IO Controls – New support for per Virtual Machine storage reservations to guarantee minimum service levels.” Is listed as one of the new features of vSphere 6.

The new mClock scheduler was introduced with vSphere 5.5 and as you might have guessed, it remains the default IO scheduler in vSphere 6 (don’t mind the typo in the description).

 

mClock advanced setting

 

Besides limits and shares, the scheduler now supports reservations. Let’s do a quick recap on resource management.