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=-3.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FSL_HELO_FAKE,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 2DA6EC433E3 for ; Sat, 15 Aug 2020 21:54:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0393C20791 for ; Sat, 15 Aug 2020 21:54:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernelim-com.20150623.gappssmtp.com header.i=@kernelim-com.20150623.gappssmtp.com header.b="MHKoo7DC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728861AbgHOVyU (ORCPT ); Sat, 15 Aug 2020 17:54:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45658 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729118AbgHOVwg (ORCPT ); Sat, 15 Aug 2020 17:52:36 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 107E0C061234 for ; Fri, 14 Aug 2020 22:45:40 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id a14so10081473wra.5 for ; Fri, 14 Aug 2020 22:45:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernelim-com.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=+/aQPgBdctfCPkN2hsKPsv6boSaHaEN13UyN4xwV5wE=; b=MHKoo7DCs5fHWAvtff6EIY7D/hJHp24zHtuKEc/vJMN5VcYuVv8I/1uMI8uaPgjtcw bBMbE8FexiGLLFxMU7gOq3y+TzLhYeKQU0RsSqJ0xGmOPlQgtDQX/SvzAWzAK68DyCgD i/LaqykKOWNw/pCN/UKF5fN6RuyVV0EfACgAOo9gWlHvY69yeqM7nS+0xzsj1W2jLWEX 8D75pzQraiu+kBy3x7UdpxjNZR49v2k02eTvFJABr6SdEyW6/DsZik92iDUbl0I1hLPs JXp3stppcDVkPvzNq+DHjsWDvRLsT5CuFzi1/hRMn+BiPC6N4gEpObmDBgKdt2qLhM/r yDXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=+/aQPgBdctfCPkN2hsKPsv6boSaHaEN13UyN4xwV5wE=; b=Mi5RB2GH2p9uFyOcur5wiM7MPeLUWg5XtyuwvtvjV4W4OftHLFz1f72wIq4jLlivKV 0oa0Gf7pmYbEK+RoMTe2vh7cdsk8y/ZRVIgzuFBgC81lFwCgsBH9UiSV9q4QWVSnPgaH CvpWKIwGqdR6//6am6DfxCLJ26uRiCUEySlIokj8P6PY9P7YpvhzkmyEiT6jyLk+vHl8 m1O6xbTDqY00QKFClXp+1WyOkrU0Ez2NiMn0vW9xQv53n2rcpYm0XNZjy/pLRJQAN/d0 KDBCRw2tkMeUxT/MRfoAmjILlLNjQahrM1MujGY/mSIJGAAPqHTDQDpDHsu0CgYf7zV6 jYnQ== X-Gm-Message-State: AOAM532OrDv2lZupUISTDL/ZoWLbwMy+yn18DCNro/i392Zar88CE2rH NxGD8Dp7Syl5vYKSdC5cQ7649A== X-Google-Smtp-Source: ABdhPJy1Ks7m4wNqY3xj2Br282e4/ffX4B8ONEyjVpIaYR5PrTlOIMUPByiKuibHFE+Oy7oMmgjPgg== X-Received: by 2002:adf:ca06:: with SMTP id o6mr5285330wrh.181.1597470339433; Fri, 14 Aug 2020 22:45:39 -0700 (PDT) Received: from gmail.com ([141.226.169.176]) by smtp.gmail.com with ESMTPSA id f124sm19635765wmf.7.2020.08.14.22.45.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 14 Aug 2020 22:45:38 -0700 (PDT) Date: Sat, 15 Aug 2020 08:45:35 +0300 From: Dan Aloni To: Chuck Lever Cc: linux-rdma , Linux NFS Mailing List Subject: Re: [PATCH] xprtrdma: make sure MRs are unmapped before freeing them Message-ID: <20200815054535.GA3337941@gmail.com> References: <20200814173734.3271600-1-dan@kernelim.com> <5B87C3B5-B73D-40FD-A813-B3929CDF7583@oracle.com> <20200814191056.GA3277556@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org On Fri, Aug 14, 2020 at 04:21:54PM -0400, Chuck Lever wrote: > > > > On Aug 14, 2020, at 3:10 PM, Dan Aloni wrote: > > > > On Fri, Aug 14, 2020 at 02:12:48PM -0400, Chuck Lever wrote: > >> Hi Dan- > >> > >>> On Aug 14, 2020, at 1:37 PM, Dan Aloni wrote: > >>> > >>> It was observed that on disconnections, these unmaps don't occur. The > >>> relevant path is rpcrdma_mrs_destroy(), being called from > >>> rpcrdma_xprt_disconnect(). > >> > >> MRs are supposed to be unmapped right after they are used, so > >> during disconnect they should all be unmapped already. How often > >> do you see a DMA mapped MR in this code path? Do you have a > >> reproducer I can try? > > > > These are not graceful disconnections but abnormal ones, where many large > > IOs are still in flight, while the remote server suddenly breaks the > > connection, the remote IP is still reachable but refusing to accept new > > connections only for a few seconds. > > Ideally that's not supposed to matter. I'll see if I can reproduce > with my usual tricks. > > Why is your server behaving this way? It's a dedicated storage cluster under a specific testing scenario, implementing floating IPs. Haven't tried, but maybe the same scenario can be reproduced with a standard single Linux NFSv3 server by fiddling with nfsd open ports. -- Dan Aloni