Re: why nfs server delay 10ms in nfsd_write()?

[Trond Myklebust]

to den 19.05.2005 Klokka 10:46 (+0800) skreiv steve:

> i have 2 questions:
> 1.i don't know why do we have to sleep for 10 ms, why not do sync immediately?
> 2.what will happen if we don't sleep for 10ms?
> when i delete these codes, i get a good result, and the write performace improved from 300KB/s to 18MB/s

See
http://www.usenix.org/publications/library/proceedings/sf94/full_papers/juszczak.a

Write gathering is basically a method for improving NFSv2 writes without
any protocol changes. Later, NFSv3 introduced the more efficient concept
of "unstable" writes into the protocol (see
http://www.netapp.com/ftp/NFSv3_Rev_3.pdf).

You can turn NFSv2 write gathering on and off using the wdelay/no_wdelay
export options ('man 5 exports')

Trond

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/