From nobody Wed Apr 06 11:42:53 2022 X-Original-To: freebsd-hackers@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 F0C211A888B5 for ; Wed, 6 Apr 2022 11:43:28 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from hz.grosbein.net (hz.grosbein.net [IPv6:2a01:4f8:c2c:26d8::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hz.grosbein.net", Issuer "hz.grosbein.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4KYN1r0Mpmz4npf for ; Wed, 6 Apr 2022 11:43:27 +0000 (UTC) (envelope-from eugen@grosbein.net) Received: from eg.sd.rdtc.ru (root@eg.sd.rdtc.ru [62.231.161.221] (may be forged)) by hz.grosbein.net (8.16.1/8.16.1) with ESMTPS id 236BhJWq054666 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 6 Apr 2022 11:43:20 GMT (envelope-from eugen@grosbein.net) X-Envelope-From: eugen@grosbein.net X-Envelope-To: egoitz@ramattack.net Received: from [10.58.0.11] (dadv@dadvw [10.58.0.11] (may be forged)) by eg.sd.rdtc.ru (8.16.1/8.16.1) with ESMTPS id 236Bgrmu090755 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Wed, 6 Apr 2022 18:43:18 +0700 (+07) (envelope-from eugen@grosbein.net) Subject: Re: Desperate with 870 QVO and ZFS To: egoitz@ramattack.net, Freebsd hackers References: <6cf6c03c5a4aa8128575ec4e2f70b168@ramattack.net> From: Eugene Grosbein Message-ID: <15a86fae-90fd-951d-50e0-48f9be8b4bbc@grosbein.net> Date: Wed, 6 Apr 2022 18:42:53 +0700 User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 In-Reply-To: <6cf6c03c5a4aa8128575ec4e2f70b168@ramattack.net> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT autolearn=disabled version=3.4.2 X-Spam-Report: * -0.0 SHORTCIRCUIT No description available. * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on hz.grosbein.net X-Rspamd-Queue-Id: 4KYN1r0Mpmz4npf X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=fail (mx1.freebsd.org: domain of eugen@grosbein.net does not designate 2a01:4f8:c2c:26d8::2 as permitted sender) smtp.mailfrom=eugen@grosbein.net X-Spamd-Result: default: False [-0.13 / 15.00]; ARC_NA(0.00)[]; R_SPF_FAIL(1.00)[-all]; FREEFALL_USER(0.00)[eugen]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; NEURAL_HAM_MEDIUM(-0.79)[-0.790]; NEURAL_HAM_LONG(-0.33)[-0.331]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[grosbein.net]; NEURAL_SPAM_SHORT(0.09)[0.089]; RCVD_COUNT_THREE(0.00)[3]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; MLMMJ_DEST(0.00)[freebsd-hackers]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:24940, ipnet:2a01:4f8::/32, country:DE]; RCVD_TLS_ALL(0.00)[]; MID_RHS_MATCH_FROM(0.00)[] X-ThisMailContainsUnwantedMimeParts: N 06.04.2022 18:18, egoitz@ramattack.net wrote: > Good morning, > > I write this post with the expectation that perhaps someone could help me :) > > I am running some mail servers with FreeBSD and ZFS. They use 870 QVO (not EVO or other Samsung SSD disks) disks as storage. They can easily have from 1500 to 2000 concurrent connections. The machines have 128GB of ram and the CPU is almost absolutely idle. The disk IO is normally at 30 or 40% percent at most. > > The problem I'm facing is that they could be running just fine and suddenly at some peak hour, > the IO goes to 60 or 70% and the machine becomes extremely slow. You should run: gstat -adpI3s And monitor all values, especially "deletes": d/s, next KBps and ms/d. If you have many delete operations (including ZFS snapshort destroying), it may result in massive chunks of TRIM operations sent to SSD. Some SSD products have abysmal TRIM performance.