Subject: Re: msdosfs performance problem
To: Michael van Elst <mlelstv@serpens.de>
From: Matthew Orgass <darkstar@city-net.com>
List: tech-kern
Date: 11/27/2005 14:59:37
On 2005-11-27 mlelstv@serpens.de wrote:

> I recently noticed that msdosfs reads from the disk when
> you write to it. The number of blocks read is almost the
> same as the number of blocks written.

  msdosfs does all writes fully synchronously (why, I can't say).  In ffs
synchronous the time field in read is the same as write (just as with
msdosfs), but the other fields are usually empty.  I think one of them may
not be doing accounting correctly (presumably msdosfs).  msdosfs appears
to get slightly better performance than ffs -o sync (on dd bs=60k write
test of 190MB to compact flash).

Matthew Orgass
darkstar@city-net.com