Hello,
I have read many NFS performance related threads on google as well in the forum, but unfortunately following all the advices my network performance is still extreamly slow.
My configuration is as follows
ESXi 5.0, Synology NAS (4 disks, RAID 5). The ESXi server has 3 Gigabit n/w interfaces (Intel 82576 Gigabit dual port & Boradcom NetXtreme BCM5722).
Network speed of all the cards matches with the CISCO switch, i.e both ends are 1000 Full Duplex
I have two virtual switches, one for virtual machine (with 2 n/w interfaces, i.e Intel 82576) and another switch for VMKernel (1 n/w interface, Boradcom BCM5722)
On ESXi console, when I try to copy say 1 GB file from NFS datastore to local datastore, I get reading speed from NFS share around 20Mbps and writting back to same share is around 5Mbps.
If I try to read/ write on another share on the same NAS using separete physical windows machine (Windows 7) having only one Gigabit n/w interface, I get reading speed around 120Mbps and writting around 50Mbps. This is total different compared to ESXi. If there is a problem with Synology NAS, I wont get such a speed while using another physical machine.
Also virtual machines running on ESXi, Windows 2008 R2, I get reading speed from another share on the same NAS is about 70Mbps and writting is around 4 Mbps. I tried using different I am using adaptor types (E1000, VMXNET3). With VMXNET 3, I get better reading speed but writting is poorly slow.
I also tried teaming all three n/w interafaces without success.
In the end, I tried installing Windows 2008 R2 on ESXi server on separete disk to check if something wrong with the physical hardware (Umaking dual boot) but surprisingly I got excellent reading / writting speed on Synology NAS without changing anything.
So I am wondering, whats going wroing with ESXi.
Any help to debug & improve the problem is highly appreciate.
Thanks,
Sameer