From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 26 Oct 2001 16:39:58 +0200 From: Jens Axboe Subject: Re: xmm2 - monitor Linux MM active/inactive lists graphically Message-ID: <20011026163958.C3324@suse.de> 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: Zlatko Calusic Cc: Linus Torvalds , Marcelo Tosatti , linux-mm@kvack.org, lkml List-ID: On Fri, Oct 26 2001, Zlatko Calusic wrote: > Linus Torvalds writes: > > > On 25 Oct 2001, Zlatko Calusic wrote: > > > > > > Yes, I definitely have DMA turned ON. All parameters are OK. :) > > > > I suspect it may just be that "queue_nr_requests"/"batch_count" is > > different in -ac: what happens if you tweak them to the same values? > > > > Next test: > > block: 1024 slots per queue, batch=341 That's way too much, batch should just stay around 32, that is fine. > Still very spiky, and during the write disk is uncapable of doing any > reads. IOW, no serious application can be started before writing has > finished. Shouldn't we favour reads over writes? Or is it just that > the elevator is not doing its job right, so reads suffer? You are probably just seeing starvation due to the very long queues. -- Jens Axboe -- 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/