From nobody Wed Jul 7 10:04:46 2021 X-Original-To: freebsd-stable@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 D66041224387 for ; Wed, 7 Jul 2021 10:04:57 +0000 (UTC) (envelope-from petefrench@ingresso.co.uk) Received: from constantine.ingresso.co.uk (constantine.ingresso.co.uk [IPv6:2001:470:6a18:411::3]) (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 did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4GKZm95lmrz4VTf; Wed, 7 Jul 2021 10:04:57 +0000 (UTC) (envelope-from petefrench@ingresso.co.uk) Received: from [2001:470:6cc4:1:cd6:5836:ddba:7b54] (helo=balta.drayhouse.twisted.org.uk) by constantine.ingresso.co.uk with esmtpsa (TLS1.3) tls TLS_AES_128_GCM_SHA256 (Exim 4.94.2 (FreeBSD)) (envelope-from ) id 1m14QD-0002dw-NP; Wed, 07 Jul 2021 10:04:49 +0000 Subject: Re: ZFS + mysql appears to be killing my SSD's To: Pete Wright , Alan Somers Cc: Stefan Esser , FreeBSD Stable Mailing List References: <89c37c3e-22e8-006e-5826-33bd7db7739e@ingresso.co.uk> <2fd9b7e4-dc75-fedc-28d7-b98191167e6b@freebsd.org> <9c71d627-55b8-2464-6cc9-489e4ce98049@ingresso.co.uk> <2e6dbe13-e08f-1dab-1f5b-76a90c3a2ea7@nomadlogic.org> From: Pete French Message-ID: Date: Wed, 7 Jul 2021 11:04:46 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 List-Id: Production branch of FreeBSD source code List-Archive: https://lists.freebsd.org/archives/freebsd-stable List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-stable@freebsd.org X-BeenThere: freebsd-stable@freebsd.org MIME-Version: 1.0 In-Reply-To: <2e6dbe13-e08f-1dab-1f5b-76a90c3a2ea7@nomadlogic.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 4GKZm95lmrz4VTf X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[] X-Spam: Yes X-ThisMailContainsUnwantedMimeParts: N On 07/07/2021 00:01, Pete Wright wrote: > i also wonder if this could be a TRIM related issue.  according to > zpoolprops(8) TRIM is not enabled by default on pools - but it also has > this note (see autotrim): > > "Be aware that automatic trimming of recently freed data blocks > can put significant stress on the underlying storage devices. > This will vary depending of how well the specific device handles > these commands.  For lower end devices it is often possible to > achieve most of the benefits of automatic trimming by running an > on-demand (manual) TRIM periodically using the zpool trim > command." > > > I wonder if adjusting the autotrim feature will address these issues - i > manually enable autotrim for my pools and have seen no bad effects under > quite of bit of bursty i/o.  if it is enabled i wonder if the ssd you > are using doesn't play nice with autotrim and should stay disabled? I was thinking this too - the autotrim stuff came in with OpenZFS, but I had trim enabled previously (I believe we had our own implementation on FreeBSD ZFS, is that right?). But I am wondering if a schduled trim might be a better option. Though the question arises as to 'how often' in that case. -pete.