From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 26 Sep 2000 07:17:52 -0600 From: yodaiken@fsmlabs.com Subject: Re: the new VMt Message-ID: <20000926071752.A22876@hq.fsmlabs.com> References: <20000925143523.B19257@hq.fsmlabs.com> <20000925150744.A20586@hq.fsmlabs.com> <20000926105423.D1638@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20000926105423.D1638@redhat.com>; from Stephen C. Tweedie on Tue, Sep 26, 2000 at 10:54:23AM +0100 Sender: owner-linux-mm@kvack.org Return-Path: To: "Stephen C. Tweedie" Cc: yodaiken@fsmlabs.com, Alan Cox , Jamie Lokier , mingo@elte.hu, Andrea Arcangeli , Marcelo Tosatti , Linus Torvalds , Rik van Riel , Roger Larsson , MM mailing list , linux-kernel@vger.kernel.org List-ID: On Tue, Sep 26, 2000 at 10:54:23AM +0100, Stephen C. Tweedie wrote: > Beancounter is a framework for user-level accounting. _What_ you > account is up to the callers. Maybe this has been a miscommunication, > but beancounter is all about allowing callers to account for stuff > before allocation, not about having the page allocation functions > themselves enforce quotas. per-user and system-wide and per-process quotas are one thing, a pre-allocate-and-then-allocate generic scheme seems to me to be a error prone way of getting there. In particular, I think it is dangerous to have a pre-count that is approximately tethered to the thing it is counting -- in the memory allocation we were discussing, you need to make sure that the pre-allocations are for memory that is really going to be allocated soon and that it is later correlated with free in some way. So, to me, a quota bounded allocate_page_table(process_id) makes much more sense then pre-allocate counting, or, even worse, a "smart" kmalloc that never fails. If the problem is unaccounted for page-tables then account for page tables and return a -EYOURPROCESSISOUTOFCONTROL so that calling kernel code can take the responsible action. -- --------------------------------------------------------- Victor Yodaiken Finite State Machine Labs: The RTLinux Company. www.fsmlabs.com www.rtlinux.com -- 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.eu.org/Linux-MM/