From nobody Mon Apr 27 10:25:10 2026 X-Original-To: questions@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 4g407k06gSz6ZrGn for ; Mon, 27 Apr 2026 10:25:22 +0000 (UTC) (envelope-from chris@cretaforce.gr) Received: from smtp1.cretaforce.gr (smtp1.cretaforce.gr [5.75.211.174]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "*.cretaforce.gr", Issuer "RapidSSL TLS RSA CA G1" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4g407h2Qwjz3WCS for ; Mon, 27 Apr 2026 10:25:20 +0000 (UTC) (envelope-from chris@cretaforce.gr) Authentication-Results: mx1.freebsd.org; dkim=pass header.d=cretaforce.gr header.s=cretaforce header.b=Sy2s9fwp; dmarc=pass (policy=none) header.from=cretaforce.gr; spf=pass (mx1.freebsd.org: domain of chris@cretaforce.gr designates 5.75.211.174 as permitted sender) smtp.mailfrom=chris@cretaforce.gr Received: from server1.cretaforce.gr (server1.cretaforce.gr [94.130.217.104]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) client-signature RSA-PSS (2048 bits)) (Client CN "*.cretaforce.gr", Issuer "RapidSSL TLS RSA CA G1" (not verified)) by smtp.cretaforce.gr (Postfix) with ESMTPS id ECDEE1FE25 for ; Mon, 27 Apr 2026 13:25:12 +0300 (EEST) Received: from smtpclient.apple (unknown [149.210.7.36]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) (Authenticated sender: chris@cretaforce.gr) by server1.cretaforce.gr (Postfix) with ESMTPSA id D0D3A25C26 for ; Mon, 27 Apr 2026 13:25:11 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cretaforce.gr; s=cretaforce; t=1777285513; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JuF7moFhzsd11nvO+qwxOkC+xHIIFoytWRX/LPCtNKA=; b=Sy2s9fwpJgH9IZcYGQ83sS6aeWVQrDMHAv8n+kudPeDhFP7fRVFNiWTyna7JVAlnC6RdiR VmVgQxluw4uSEToLdZy3zHDsFxBPxQwJrenTZ8JPbcZ2QX8TbxmCcpViVvL3kNsrs125lk mCiMYEaaMgoNZOkIksVPafxMTh/P2UQ= From: Christos Chatzaras Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable List-Id: User questions List-Archive: https://lists.freebsd.org/archives/freebsd-questions List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: freebsd-questions@freebsd.org Sender: owner-freebsd-questions@FreeBSD.org Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3864.400.21\)) Subject: Re: 14.4 High CPU ARC issue Date: Mon, 27 Apr 2026 13:25:10 +0300 References: <5e2170f3-a789-48c8-8bd8-4dfbd842602c@ifdnrg.com> To: questions@freebsd.org In-Reply-To: <5e2170f3-a789-48c8-8bd8-4dfbd842602c@ifdnrg.com> Message-Id: <173F9AF4-E708-4D18-8A8F-F7D571C707E9@cretaforce.gr> X-Mailer: Apple Mail (2.3864.400.21) X-Spamd-Result: default: False [-4.00 / 15.00]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_HAM_SHORT(-1.00)[-0.998]; DMARC_POLICY_ALLOW(-0.50)[cretaforce.gr,none]; R_SPF_ALLOW(-0.20)[+ip4:5.75.211.174]; R_DKIM_ALLOW(-0.20)[cretaforce.gr:s=cretaforce]; MIME_GOOD(-0.10)[text/plain]; DKIM_TRACE(0.00)[cretaforce.gr:+]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_ONE(0.00)[1]; TO_MATCH_ENVRCPT_ALL(0.00)[]; ARC_NA(0.00)[]; FREEFALL_USER(0.00)[chris]; RCVD_VIA_SMTP_AUTH(0.00)[]; MIME_TRACE(0.00)[0:+]; TO_DN_NONE(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; ASN(0.00)[asn:24940, ipnet:5.75.128.0/17, country:DE]; PREVIOUSLY_DELIVERED(0.00)[questions@freebsd.org]; MID_RHS_MATCH_FROM(0.00)[]; MLMMJ_DEST(0.00)[questions@freebsd.org]; APPLE_MAILER_COMMON(0.00)[]; DWL_DNSWL_NONE(0.00)[cretaforce.gr:dkim] X-Rspamd-Queue-Id: 4g407h2Qwjz3WCS X-Spamd-Bar: --- > On 27 Apr 2026, at 12:18, Paul Macdonald wrote: >=20 > Posting in case it helps someone. >=20 > We had a a couple of boxes displaying unusally high cpu ( specifically = system loads) >=20 > After spotting the link below, we resolved by increasing the ARC max >=20 > = https://forums.freebsd.org/threads/high-cpu-and-severe-slowdown-on-freebsd= -14-4-openzfs-2-2-9-with-lower-vfs-zfs-arc-max.102233/ I am the one who created that FreeBSD forum thread. I also opened a bug = report with OpenZFS here: https://github.com/openzfs/zfs/issues/18397 In my case, to fix the issue I disabled setting a custom value for = vfs.zfs.arc.max=