Re: large files unnecessary trashing filesystem cache?

[Badari Pulavarty <pbadari@gmail.com>]

On Wed, 2005-10-19 at 00:10 -0400, Lee Revell wrote:
> On Tue, 2005-10-18 at 22:01 +0200, Guido Fiala wrote:
> > Of course one could always implement f_advise-calls in all
> > applications
> 
> Um, this seems like the obvious answer.  The application doing the read
> KNOWS it's a streaming read, while the best the kernel can do is guess.
> 
> You don't really make much of a case that fadvise can't do the job.

The issue is, how will "other/random" programs/applications affect 
performance of my application.

Complain I hear most is from our database folks, they tune stuff
and they are happy with their performance. And then, some one does 
a tar/cp/cpio/ftp/backup/compile on some random files on the system.
Suddenly, database performance drops. They want to see a system wide/
per-filesystem tunable on how much pagecache it takes up.

Andrew, does this make sense at all ?


Thanks,
Badari