cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
1488
Views
0
Helpful
2
Replies

10Gbe : Slow read speed from NAS

Intrastucuture:

9x3750E stacked switch (WS-C3750E-48PD-SF0) (15.0(1)SE2            C3750E-UNIVERSALK9-M)

2x10Gbe uplinks from EMC NAS

At a basic level, we have found that the 10Gbe uplinks have slow read performance with or without a port-channel configured (2-3 minutes for a 700MB file to desktop from the NAS) We switched back to testing a 1Gbe and the read speed is normal. Another anomaly is Win7 / 2008 machines read speed is fine from the NAS  while the 10Gbe uplinks are in production?!

Write speed is great on 10Gbe. Only read speed is affected!!


The switch is not reporting anything abnormal. We looked at SMB/SMB2 as another possible cause...

mls qos is enabled on the switch but not sure if this is affecting performance.

Is the ANY config that I need to carry out on the interfaces to get the read speed working as it should for both Win7 and WinXP. (MTU is 1500 throughout the enterprise, NAS included).

Thanks.

2 Replies 2

dominic.caron
Level 5
Level 5

This is a typical speed missmatch problem. Take a host that is having problem and try to lower the tcp window size.

Uber
Level 1
Level 1

I seem to have the same NFS read perf issue with our 10gbe uplinked EMC VNX NAS and our 3750X stacked switches. Has anyone found a solution to this problem? I believe the window sizes are dynamic on the VNX and our linux  NFS clients.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: