From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 16 Aug 2004 17:33:22 -0300 From: Marcelo Tosatti Subject: Re: use for page_state accounting fields Message-ID: <20040816203322.GA21796@logos.cnet> References: <20040816192941.GB21238@logos.cnet> <20040816143149.510a2f90.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040816143149.510a2f90.akpm@osdl.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-mm@kvack.org List-ID: On Mon, Aug 16, 2004 at 02:31:49PM -0700, Andrew Morton wrote: > Marcelo Tosatti wrote: > > > > Hi Andrew, > > > > I suppose you wrote the page_state per-CPU statistics structure. > > > > There are some fields, for instance pgactivate/pgdeactivate, that > > do not seem to be used anywhere. Sure, they are useful for statistics, > > but no place in the kernel exports them to userspace AFAICS. > > > > unsigned long pgactivate; /* pages moved inactive->active */ > > unsigned long pgdeactivate; /* pages moved active->inactive */ > > > > Counting them is somewhat expensive I believe (need to disable IRQ), based > > on the assumption that these days any cycle is a loss. > > > > So, from my POV we should > > > > a) export them to userspace > > b) surround them by CONFIG_DEBUG_MMSTATS or something similar > > > > Tell me I'm wrong. > > Take a peek in /proc/vmstat ;) Doh. Is there any tool which reads these statistics and makes use of them? Number of inactivations/activations per timeframe, etc? Thanks -- 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/ . Don't email: aart@kvack.org