lkml.org 
[lkml]   [2001]   [Aug]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [resent PATCH] Re: very slow parallel read performance
On Mon, 27 Aug 2001, Alex Bligh - linux-kernel wrote:

> A nit: I think it's a MRU list you want.

Absolutely, however ...

> If you are reading
> ahead (let's have caps for a page that has been used for reading,
> as well as read from the disk, and lowercase for read-ahead that
> has not been used):
> ABCDefghijklmnopq
> | |
> read disk
> ptr head
> and you want to reclaim memory, you want to drop (say) 'pq'
> to get
> ABCDefghijklmno
> for two reasons: firstly because 'efg' etc. are most likely
> to be used NEXT, and secondly because the diskhead is nearer
> 'pq' when you (inevitably) have to read it again.

This is NOT MRU, since p and q have not been used yet.
In this example you really want to drop D and C instead.

regards,

Rik
--
IA64: a worthy successor to i860.

http://www.surriel.com/ http://distro.conectiva.com/

Send all your spam to aardvark@nl.linux.org (spam digging piggy)

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

\
 
 \ /
  Last update: 2005-03-22 12:58    [W:1.171 / U:0.716 seconds]
©2003-2014 Jasper Spaans. Advertise on this site