Bad performance of 7.0 nfs client with Solaris nfs server

Chuck Swiger cswiger at
Wed Feb 20 18:35:36 UTC 2008


On Feb 20, 2008, at 3:23 AM, Valerio Daelli wrote:
> 	99904 total packets received
[ ... ]
> 	61441 fragments received

[ ... ]
> 	34819 output datagrams fragmented
> 	208914 fragments created

Take a look at the level of packet fragmentation you are encountering;  
yes, this is expected and things will work but there is extra latency  
added when the IP stack has to reassemble packets before the data can  
be delivered.  Try setting the NFS rsize/wsize to 1024 or perhaps 1400  
and see whether that improves performance.

Or, if your switch and NICs support it, see whether you can get Gb  
Ethernet jumbo frames working so that you don't have to fragment for  
2K or 4K data packets....


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