From owner-freebsd-current@freebsd.org Fri Feb 5 15:05:11 2016 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 04385A9AC1B for ; Fri, 5 Feb 2016 15:05:11 +0000 (UTC) (envelope-from vangyzen@FreeBSD.org) Received: from smtp.vangyzen.net (hotblack.vangyzen.net [199.48.133.146]) by mx1.freebsd.org (Postfix) with ESMTP id D7B19C3F; Fri, 5 Feb 2016 15:05:10 +0000 (UTC) (envelope-from vangyzen@FreeBSD.org) Received: from ford.vangyzen.net (unknown [76.164.15.242]) by smtp.vangyzen.net (Postfix) with ESMTPSA id 68435564A4; Fri, 5 Feb 2016 09:05:04 -0600 (CST) Subject: Re: Kernel memory leak with x11/nvidia-driver To: Mark Johnston References: <56B230CB.3050600@FreeBSD.org> <56B3E0B4.4090603@FreeBSD.org> <20160205020543.GA1661@wkstn-mjohnston.west.isilon.com> Cc: FreeBSD Current From: Eric van Gyzen Message-ID: <56B4BA1C.5020507@FreeBSD.org> Date: Fri, 5 Feb 2016 09:05:00 -0600 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <20160205020543.GA1661@wkstn-mjohnston.west.isilon.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Feb 2016 15:05:11 -0000 On 02/ 4/16 08:05 PM, Mark Johnston wrote: > On Thu, Feb 04, 2016 at 05:37:24PM -0600, Eric van Gyzen wrote: >> On 02/ 3/16 10:54 AM, Eric van Gyzen wrote: >>> I just set up a new desktop running head with x11/nvidia-driver. I've >>> discovered a memory leak where pages disappear from the queues, never to >>> return. Specifically, the total of >>> v_active_count >>> v_inactive_count >>> v_wire_count >>> v_cache_count >>> v_free_count >>> drops, eventually becoming /much/ less than v_page_count. After leaving >>> xscreensaver running overnight, cycling the saver every 10 minutes, the >>> system was unusable, because it only had a few MB of memory. (It has 8 >>> GB physical.) >> In case anyone is curious, /usr/local/bin/xscreensaver-hacks/glmatrix >> triggers a fairly fast leak--around 600 pages per second. > I'm able to repro this on my workstation. With DTrace I can see that > glmatrix is allocating pages for an SG object at roughly the rate > they're being leaked. I took a look at r292373 (based on the history of > sg_pager.c) and noticed a vm_page_free() call was lost when > sg_pager_getpages() was simplified. > > The patch below seems to do the trick for me. Could you give it a try > and confirm that it fixes the problem? I run current+nvidia-driver on > multiple workstations but hadn't observed a leak until now, so maybe > there's something additional going on in your case. Then again, I just > use i3lock. :) > > diff --git a/sys/vm/sg_pager.c b/sys/vm/sg_pager.c > index 84bfa49..2cccb7ea 100644 > --- a/sys/vm/sg_pager.c > +++ b/sys/vm/sg_pager.c > @@ -189,6 +189,9 @@ sg_pager_getpages(vm_object_t object, vm_page_t *m, int count, int *rbehind, > VM_OBJECT_WLOCK(object); > TAILQ_INSERT_TAIL(&object->un_pager.sgp.sgp_pglist, page, plinks.q); > vm_page_replace_checked(page, object, offset, m[0]); > + vm_page_lock(m[0]); > + vm_page_free(m[0]); > + vm_page_unlock(m[0]); > m[0] = page; > page->valid = VM_PAGE_BITS_ALL; > Your patch fixes the leak completely. Nice work, Mark! I didn't notice the leak until I unknowingly left the screensaver cycling all overnight. In my normal workflow, I open the windows I need and pretty much leave them there. This doesn't seem to trigger the leak, at least not at a noticeable rate. Thanks for your help! Eric