From owner-freebsd-hackers@freebsd.org Sat Dec 16 19:47:58 2017 Return-Path: Delivered-To: freebsd-hackers@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 C7A9BE8CA67 for ; Sat, 16 Dec 2017 19:47:58 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: from asp.reflexion.net (outbound-mail-210-96.reflexion.net [208.70.210.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 7422470132 for ; Sat, 16 Dec 2017 19:47:57 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: (qmail 22626 invoked from network); 16 Dec 2017 18:47:51 -0000 Received: from unknown (HELO mail-cs-01.app.dca.reflexion.local) (10.81.19.1) by 0 (rfx-qmail) with SMTP; 16 Dec 2017 18:47:51 -0000 Received: by mail-cs-01.app.dca.reflexion.local (Reflexion email security v8.40.3) with SMTP; Sat, 16 Dec 2017 13:47:51 -0500 (EST) Received: (qmail 22848 invoked from network); 16 Dec 2017 18:47:51 -0000 Received: from unknown (HELO iron2.pdx.net) (69.64.224.71) by 0 (rfx-qmail) with (AES256-SHA encrypted) SMTP; 16 Dec 2017 18:47:51 -0000 Received: from [192.168.1.25] (c-76-115-7-162.hsd1.or.comcast.net [76.115.7.162]) by iron2.pdx.net (Postfix) with ESMTPSA id C2D4CEC7848; Sat, 16 Dec 2017 10:47:50 -0800 (PST) From: Mark Millard Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: faq/troubleshoot.html#indefinite-wait-buffer has the direction of transfer wrong (head -r326888 /usr/src/) Message-Id: Date: Sat, 16 Dec 2017 10:47:50 -0800 To: FreeBSD Hackers , FreeBSD Current X-Mailer: Apple Mail (2.3273) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 16 Dec 2017 19:47:58 -0000 I got a "swap_pager: indefinite wait buffer" notice and looked it up. (This was on a rpi2 booted (kernel and world) from a USB SSD, swap partition in use instead of a swap file. It was building devel/cmake via poudriere-devel .) https://www.freebsd.org/doc/faq/troubleshoot.html#indefinite-wait-buffer reads like it is for page-out to disk: QUOTE 5.9. What does the error swap_pager: indefinite wait buffer: mean? This means that a process is trying to page memory to disk, and the page = attempt has hung trying to access the disk for more than 20 seconds. It = might be caused by bad blocks on the disk drive, disk wiring, cables, or = any other disk I/O-related hardware. If the drive itself is bad, disk = errors will appear in /var/log/messages and in the output of dmesg. = Otherwise, check the cables and connections. ENDQUOTE But the code containing the message is for "swread": (head -r326888) # grep -r "indefinite wait buffer" /usr/src/sys/ | more /usr/src/sys/vm/swap_pager.c:"swap_pager: indefinite wait buffer: = bufobj: %p, blkno: %jd, size: %ld\n", Looking there. . . static int swap_pager_getpages(vm_object_t object, vm_page_t *m, int count, int = *rbehind, int *rahead) { . . . VM_OBJECT_WLOCK(object); while ((m[0]->oflags & VPO_SWAPINPROG) !=3D 0) { m[0]->oflags |=3D VPO_SWAPSLEEP; VM_CNT_INC(v_intrans); if (VM_OBJECT_SLEEP(object, &object->paging_in_progress, = PSWP, "swread", hz * 20)) { printf( "swap_pager: indefinite wait buffer: bufobj: %p, blkno: %jd, size: = %ld\n", bp->b_bufobj, (intmax_t)bp->b_blkno, = bp->b_bcount); } } . . . =3D=3D=3D Mark Millard markmi at dsl-only.net