NFS - slow

Wojciech Puchar wojtek at
Fri Apr 27 20:05:46 UTC 2012

is there any way to speed up NFS server?

from what i noticed:

- reads works fast and good, like accessed locally, readahead up to 
maxbsize works fine on large files etc.

- write works terribly. it performs sync on every write IMHO,
setting vfs.nfsrv.async=1 improves things SLIGHTLY, but still - writes are 
sent to hard disk every single block  - no clustering.

am i doing something wrong or is it that broken?

i tried user space nfs from ports, it's funny but it's performance is 
actually better after i removed fsync from code.

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