[DSS V7][JovianDSS] I have a low NFS performance in VMware environment.

Additional information:

• product name: JovianDSS / DSS V7
• product version: all
• build: all 

Problem:

"I have a low NFS performance in VMware environment."
Customer reports that NFS performance results for NFS 16K writes are ~11 MB/sec.

Symptoms:

Tests conducted with DSS and IOMeter: while doing 16K Reads and with parameters as specified in "Comparison of Storage Protocol Performance" documentation from VMware, Read performance for iSCSI and NFS is ~110 MB/sec.  Also, while performance for 16K Writes on iSCSI is ~70 MB/sec, NFS Write performance is very slow.

Solution:

Unchecking "Synchronous" box and running IOMeter Write test reports ~100 MB/sec for NFS - same as for iSCSI. Also, cloning 8 GB test VM and gives results comparable to same operation performed via iSCSI - just under 3 minutes or 50 MB/sec.