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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DA11C433F5 for ; Wed, 16 Mar 2022 15:26:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236203AbiCPP1W (ORCPT ); Wed, 16 Mar 2022 11:27:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36368 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229528AbiCPP1W (ORCPT ); Wed, 16 Mar 2022 11:27:22 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id DE02314005 for ; Wed, 16 Mar 2022 08:26:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1647444367; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Fiyi0AzB53E81OTo2YZCLg9th3nDyr7cwTlg8VafXOo=; b=iT1zn706wWkQR5mJSJmwXlQprwOWFgK2uqMBU6xJ6jq3LFlOf1oG7B1uxwoDTkgC1BNSVI 869XzZhPYftq46iqoI8qlbS3k2IOWyr0qTybeTJ3Maz3tBlMFO/QWdEf2RWwhfi/PP1Moi fNvXhrynkPb46XlkYESoPpB50tuJaRk= Received: from mail-oo1-f72.google.com (mail-oo1-f72.google.com [209.85.161.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-636-D7piYzEqOJuAQccQuU0FZw-1; Wed, 16 Mar 2022 11:26:05 -0400 X-MC-Unique: D7piYzEqOJuAQccQuU0FZw-1 Received: by mail-oo1-f72.google.com with SMTP id o68-20020a4a4447000000b003210ddc07a2so1584940ooa.6 for ; Wed, 16 Mar 2022 08:26:05 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:mime-version:content-transfer-encoding; bh=Fiyi0AzB53E81OTo2YZCLg9th3nDyr7cwTlg8VafXOo=; b=qVFTroUM+xcj1fuyPIydO05TOIkqXR0DsaqrmgPyIEh8BtA77V/9gF2KGMrUM7H8cI Ol1YlcgvYnaaRjcctT2Wfn0zQ+VtIAU/bY7fSubT7h+KMmJNkU38UFPQZEKkc+moOGoc zkTdp5zsotOMvXK2vhiagubAE053aysitWsv0taxfnuCT9f0V+UsnykGmwUY1dBUB7dh YAwU9FS3CZgGbiOxYsRk2RvSfDkTeyxHq8V3jHIB9ptAij6BQpBxMINtvY2P2diP1162 b2u1aHyB8NeFbSwR3c+x96QTOPBCpuEHpk9QtVHcz6XENeWhalIIwK7mzlocHhW86zX0 RKbQ== X-Gm-Message-State: AOAM530ldYZZ0ynVrHqaUOkIva+mODGiO/kNkZvMgniGAFK+wuRiGPhv EPlieydvp/3mHxCU/zm+666NQZzlYFmJ3Ab8yYE/l9MBmQdVAq2gEKkJnKh71o5PDBNd4CyWxQD Q5/Pie6guMfS5Ss0waHbbkAuS X-Received: by 2002:a05:6870:e3c1:b0:d7:2dc8:7fd0 with SMTP id y1-20020a056870e3c100b000d72dc87fd0mr114715oad.104.1647444365075; Wed, 16 Mar 2022 08:26:05 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzd5CO1nlVAFAAJNB90SULBwx2B6wh4kD1JZowYmjPzUhrIR+VsY+TYRoYNtuFzS4AbCfRi2Q== X-Received: by 2002:a05:6870:e3c1:b0:d7:2dc8:7fd0 with SMTP id y1-20020a056870e3c100b000d72dc87fd0mr114708oad.104.1647444364838; Wed, 16 Mar 2022 08:26:04 -0700 (PDT) Received: from loberhel ([2600:6c64:4e7f:cee0:729d:61b6:700c:6b56]) by smtp.gmail.com with ESMTPSA id c6-20020a056830314600b005ca1bb396dfsm991322ots.32.2022.03.16.08.26.03 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 16 Mar 2022 08:26:04 -0700 (PDT) Message-ID: Subject: Re: [Patch 0/2] iscsit/isert deadlock prevention under heavy I/O From: Laurence Oberman To: Sagi Grimberg , Max Gurtovoy , David Jeffery Cc: linux-rdma@vger.kernel.org, target-devel@vger.kernel.org Date: Wed, 16 Mar 2022 11:26:03 -0400 In-Reply-To: <165698e9-9ccd-c840-b926-48f2ee7c6dcb@grimberg.me> References: <20220311175713.2344960-1-djeffery@redhat.com> <720ebd1f98ab3c709443176011f51d6e3ed37272.camel@redhat.com> <165698e9-9ccd-c840-b926-48f2ee7c6dcb@grimberg.me> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5 (3.28.5-10.el7) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org On Wed, 2022-03-16 at 16:39 +0200, Sagi Grimberg wrote: > Is there any measure-able performance implication? >From our testing and customers it prevented the deadlock, but did not seem to incur any additional latency. I was reaching similar IOPS/sec amd GB/sec prior to deadlock. The benefit seems to be just no more stalls and hung tasks Thanks for the replies Kind Regards Laurence