2004-09-14 23:55:24

by Bruce Allan

[permalink] [raw]
Subject: client breaking large synchronous writes into page-sized operations

Hi Trond,

>From the FAQ, the answer to B9 states:
Currently the Linux NFS client has a limitation which prevents it from
safely generating large synchronous writes. The client breaks large write
requests into on-the-wire write operations that are no larger than a
single page to guarantee that write requests arrive on the server's disk
in byte order (some applications depend on this behavior). Even if you set
wsize larger than a page, the client will break any application write
request into page-sized NFS write operations to meet this guarantee.

I was wondering if you could explain what the limitation is.

Regards,
---
Bruce Allan <[email protected]>
Software Engineer, Linux Technology Center
IBM Corporation, Beaverton OR
503-578-4187 IBM Tie-line 775-4187



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2004-09-15 09:16:44

by Trond Myklebust

[permalink] [raw]
Subject: Re: client breaking large synchronous writes into page-sized operations

P=E5 on , 15/09/2004 klokka 01:55, skreiv Bruce Allan:

> I was wondering if you could explain what the limitation is.
>=20

The limitation is that writepage and friends all work using single
pages.

It is therefore not an NFS client limitation, it is a VFS limitation...

Cheers,
Trond



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