[prev in list] [next in list] [prev in thread] [next in thread] 

List:       reiserfs-devel
Subject:    (reiserfs) Re: Two questions
From:       "Stephen C. Tweedie" <sct () redhat ! com>
Date:       1999-08-17 20:09:37
[Download RAW message or body]

Hi,

On Mon, 16 Aug 1999 23:07:51 +0100 (GMT), Matthew Kirkwood
<weejock@ferret.lmh.ox.ac.uk> said:

> We discussed this for a while, and he seems to think that W2K is
> returning immediately on (significant) writes, and doing MMU tricks
> to block if the application tries to access that buffer before the
> read has completed.

Hmm?  On Linux, the writes go straight to cache, so there is no
blocking, and the disk IO takes place in the background anyway.  There
is simply no cheap way to do page table MMU tricks for threaded
processes on SMP boxes, btw, as you have to do inter-CPU interrupts to
invalidate TLBs, so such VM tricks are always going to have cases
where they can't be used.

--Stephen

[prev in list] [next in list] [prev in thread] [next in thread]