Subject: Re: Throttling IO Requests in NetBSD via Congestion Control
To: None <tls@rek.tjls.com>
From: Jason Thorpe <thorpej@shagadelic.org>
List: tech-kern
Date: 08/21/2006 14:15:07
On Aug 21, 2006, at 12:47 PM, Thor Lancelot Simon wrote:

> I guess I'm confused.  How, exactly, do we measure the maximum  
> aggregate
> operations/sec throughput of the disk?  There should be no upper bound
> on the write throughput unless we reach that number, because writers
> should never be put to sleep.  Is that not the case?

There's another reason to implement congestion control, as posited by  
Bill Sommerfeld some years ago on this list.. and that is to ensure  
that pages are dirtied (by writing to files) no faster than they can  
be cleaned (more or less -- obviously, there is a little more too it  
than that :-)

-- thorpej