From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.3 required=3.0 tests=BAYES_05,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ECCC0C4338F for ; Sat, 24 Jul 2021 18:49:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BF82360E8E for ; Sat, 24 Jul 2021 18:49:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229873AbhGXSI5 (ORCPT ); Sat, 24 Jul 2021 14:08:57 -0400 Received: from michael-notr.mail.tiscali.it ([213.205.33.216]:49332 "EHLO smtp.tiscali.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S229530AbhGXSI5 (ORCPT ); Sat, 24 Jul 2021 14:08:57 -0400 X-Greylist: delayed 500 seconds by postgrey-1.27 at vger.kernel.org; Sat, 24 Jul 2021 14:08:56 EDT Received: from chirone.localnet ([151.27.243.99]) by michael.mail.tiscali.it with id Z6h72500329PK4v016h7Hp; Sat, 24 Jul 2021 18:41:07 +0000 x-auth-user: gianfrus@tiscali.it From: Gianluca Frustagli To: linux-raid@vger.kernel.org Subject: SSD based sw RAID: is ERC/TLER really important? Date: Sat, 24 Jul 2021 20:41:06 +0200 Message-ID: <2232919.g0K5C1TF2C@chirone> User-Agent: KMail/4.14.10 (Linux/3.16.7-53-desktop; KDE/4.14.9; x86_64; ; ) MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tiscali.it; s=smtp; t=1627152067; bh=0QFps8p0WEmIAmrW0MEgyXHNPF7nI+Un88pTN/KN8WM=; h=From:To:Subject:Date; b=qy28VjssubuKYuODQMm7cPHEkLChQzXZHEElk4qd1DdO3iN+5DsizCLxz3vYA22t0 4QokMo9o0uH9rC57laKrXqTMAssZWYBZKtvhItKZjpkuN2uPvHpvWcwJsj5KP3mfP1 EvULXFMacHMeXj6XuL2U1DGh3vMlgSRmFdM898Dw= Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org Hi, nowadays we all know that the ERC/TLER capability is very important for the use of spinning drives in RAID systems because, especially for recent hard disks, the recovery time in case of media errors could exceed kernel timeouts and possibly kick off the entire drive from the RAID set and, in turn, lead to a fault of a RAID5 system upon a subsequent error in a second drive. But in the case of SSD drives (where, possibly, the error recovery activities performed by the drive firmware are very fast) does the presence of the ERC/TLER capability really matter? Is the same scenario from the spinning drives case actually even probable or only theorical? Thank you for the considerations and evaluations you want to express. Gianluca