From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 21 Nov 2002 17:08:53 -0800 From: William Lee Irwin III Subject: Re: 2.5.48-mm1 Message-ID: <20021122010853.GI11776@holomorphy.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org Return-Path: To: Bill Davidsen Cc: Hugh Dickins , lkml , linux-mm@kvack.org List-ID: On Thu, Nov 21, 2002 at 04:04:25PM -0500, Bill Davidsen wrote: > This is purely a performance decision. If you want to avoid bad latency on > reads then you have to throttle writes. The loop_thread will make the > system just as slow as a user application writing the same number of > pages. > If you want io scheduling you will deliberately slow writes to let reads > happen in reasonable time. And vice-versa I imagine, although I don't > think I've seen that case. Not entirely so. This is just a scheduling decision that has to discriminate between blocking and nonblocking requests and prevent starvation of the blocking requests. Write throttling is an oversimplification that functions poorly. Bill -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/