Subject: Re: UBC status
To: None <>
From: Neil A. Carson <>
List: tech-kern
Date: 09/30/1999 10:58:32
"Eduardo E. Horvath" wrote:

> Interesting....  I think that Sun is still having problems with the
> 2-handed clock algorithm they use for page scanning.  We may be able to
> get a similar effect by adding a separate active or inactive list for
> buffer cache pages.

I am very surprised Sun uses a 2-hand clock algorithm! I thought all of
these were dead and burried. Even Linux recently moved to a page-lru
algorithm recently. Of course that too can be improved upon. There are
lots of papers floating on improvement with reference to database page

> What if we always keep buffer-cache pages on the inactive list (unless
> dirty, I suppose).  If they are accessed, move them to the end of the
> list, but don't migrate them to the active list.  Then buffer cache pages
> would have a higher rate of re-use than other pages.

What about a seperate list for cache pages?