From nobody Tue Nov 23 20:17:18 2021 X-Original-To: freebsd-fs@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id BF46A18956AE for ; Tue, 23 Nov 2021 20:17:38 +0000 (UTC) (envelope-from cross+freebsd@distal.com) Received: from relay.wiredblade.com (relay.wiredblade.com [168.235.105.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4HzFmy2Zt9z4V5s; Tue, 23 Nov 2021 20:17:38 +0000 (UTC) (envelope-from cross+freebsd@distal.com) Received: from mail.distal.com (pool-108-48-165-176.washdc.fios.verizon.net [108.48.165.176]) by relay.wiredblade.com with ESMTPSA (version=TLSv1.2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256) ; Tue, 23 Nov 2021 20:17:21 +0000 Received: from smtpclient.apple ( [2001:420:c0c4:1006::505]) by tristain.distal.com (OpenSMTPD) with ESMTPSA id 88f330ee (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Tue, 23 Nov 2021 15:17:19 -0500 (EST) Content-Type: text/plain; charset=utf-8 List-Id: Filesystems List-Archive: https://lists.freebsd.org/archives/freebsd-fs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-fs@freebsd.org Mime-Version: 1.0 (Mac OS X Mail 15.0 \(3693.20.0.1.32\)) Subject: Re: swap_pager: cannot allocate bio From: Chris Ross In-Reply-To: Date: Tue, 23 Nov 2021 15:17:18 -0500 Cc: Andriy Gapon , Mark Johnston , freebsd-fs Content-Transfer-Encoding: quoted-printable Message-Id: <42CC8B5C-1E08-4EE4-8CCE-4EC959C60BD1@distal.com> References: <9FE99EEF-37C5-43D1-AC9D-17F3EDA19606@distal.com> <09989390-FED9-45A6-A866-4605D3766DFE@distal.com> <4E5511DF-B163-4928-9CC3-22755683999E@distal.com> <19A3AAF6-149B-4A3C-8C27-4CFF22382014@distal.com> <6DA63618-F0E9-48EC-AB57-3C3C102BC0C0@distal.com> <35c14795-3b1c-9315-8e9b-a8dfad575a04@FreeBSD.org> <471B80F4-B8F4-4D5A-9DEB-3F1E00F42A68@distal.com> To: Ronald Klop X-Mailer: Apple Mail (2.3693.20.0.1.32) X-Rspamd-Queue-Id: 4HzFmy2Zt9z4V5s X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; TAGGED_FROM(0.00)[freebsd] X-ThisMailContainsUnwantedMimeParts: N > On Nov 23, 2021, at 06:18, Ronald Klop via freebsd-fs = wrote: >=20 > Just a wild guess. Would it help if you set a limit in the = vfs.zfs.arc_max variable? > Maybe that will help lower the memory pressure and gain some = stability. > You can use the zfs-stats package to see the current ARC size. >=20 > My RPI4 gives: > # zfs-stats -A > ... > ARC Size: 28.19% 1.93 GiB > Target Size: (Adaptive) 30.47% 2.08 GiB > Min Size (Hard Limit): 3.58% 250.80 MiB > Max Size (High Water): 27:1 6.84 GiB > ... >=20 > You can use your stats to tune it to not use too much memory for ARC = and leave more for the running applications so swapping might also be = reduced. >=20 > You can check zfs-stats -E to see if the ARC cache hit ratio is still = ok with limited ARC. Thanks for that detail regarding zfs-stats. Someone else had suggested = limiting arc_max, but the concern was that it might just mask the real problem. = It was my fallback plan, though, if we couldn=E2=80=99t make progress towards = avoiding the lock-up. - Chris=