Subject: Re: msdosfs performance problem
To: Michael van Elst <>
From: Matthew Orgass <>
List: tech-kern
Date: 11/27/2005 16:55:45
On 2005-11-27 wrote:
> (Matthew Orgass) writes:
> >  msdosfs does all writes fully synchronously (why, I can't say).
> As I understand it meta data writes are synchronous but
> can be asynchronous if you mount -o async. Data writes
> are done by UBC and are asynchronous.

  You are right, it isn't fully synchronous. I should have tested it more
(checking directly now does show serious performance loss with -o sync).
However it doesn't seem to behave quite like normal ffs in that all data
will be flushed before the writing command completes, and dd seems to show
accurate times early in the transfer.

Matthew Orgass