From owner-freebsd-current@freebsd.org Thu May 21 06:59:04 2020 Return-Path: Delivered-To: freebsd-current@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id BC58832B87D for ; Thu, 21 May 2020 06:59:04 +0000 (UTC) (envelope-from rlibby@gmail.com) Received: from mail-qt1-f178.google.com (mail-qt1-f178.google.com [209.85.160.178]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 49SL7q739Pz4V8c; Thu, 21 May 2020 06:59:03 +0000 (UTC) (envelope-from rlibby@gmail.com) Received: by mail-qt1-f178.google.com with SMTP id p12so4682004qtn.13; Wed, 20 May 2020 23:59:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=5U4BHeNFicaawlgNtbUTsTB4ZHJ2JKZAhV6iPalujVk=; b=Kywmtwn3RmMRwFtaNbzT2sbXHFpWnJybQ5k+SEArOmt34Vvqz9GOUEPURKZ8z4vS0c bylcruVdYJCnx5l1QsdsSIjUYAzptY7Q4iFovvpAtjaS4tSGLwvqbJmBcwCSCHo2uv91 O5E8QoHj3IwvptWjZzMEL2Mg019QdRzBbYq/m0GWWtwj/uiKpajHqBvcSqL86VyT9cnN viYsZG7ALF74fTw0Njw4D6TyWDfxseesDLQc/2cboWQOVzZyB7oxgKGtisjlIgwD3jf8 dkfdg9y0+koWrSLEbEWuH/MYWnt+VxNhlxLfaKvQ3Hk4S/Gq4ArFVQKdUC6zmKcN1wSm sDkw== X-Gm-Message-State: AOAM53019VZylOTdWwNV8xJS8lQlaTXxoiAbPcb2CBTBWVlwtSSbbBld /pU5t7krqf9lUT/KcGQ2wA2TqTwm X-Google-Smtp-Source: ABdhPJz825IW8yntPy7b102j0rBupwcOfDM2Ga/WEVrsCiGqiKzyeT0KbZjYswE2lugrRgRHIOYWAw== X-Received: by 2002:ac8:1af3:: with SMTP id h48mr8780296qtk.371.1590044342386; Wed, 20 May 2020 23:59:02 -0700 (PDT) Received: from mail-qt1-f174.google.com (mail-qt1-f174.google.com. [209.85.160.174]) by smtp.gmail.com with ESMTPSA id f7sm4206253qtg.96.2020.05.20.23.59.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 May 2020 23:59:01 -0700 (PDT) Received: by mail-qt1-f174.google.com with SMTP id m64so4730027qtd.4; Wed, 20 May 2020 23:59:01 -0700 (PDT) X-Received: by 2002:ac8:3968:: with SMTP id t37mr9053586qtb.174.1590044341606; Wed, 20 May 2020 23:59:01 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Ryan Libby Date: Wed, 20 May 2020 23:58:50 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: r358252 causes intermittent hangs where processes are stuck sleeping on btalloc To: Rick Macklem Cc: "freebsd-current@FreeBSD.org" , Konstantin Belousov Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 49SL7q739Pz4V8c X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of rlibby@gmail.com designates 209.85.160.178 as permitted sender) smtp.mailfrom=rlibby@gmail.com X-Spamd-Result: default: False [-1.71 / 15.00]; TO_DN_EQ_ADDR_SOME(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:209.85.128.0/17]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[freebsd.org]; ARC_NA(0.00)[]; RWL_MAILSPIKE_GOOD(0.00)[209.85.160.178:from]; NEURAL_HAM_LONG(-0.30)[-0.302]; RCVD_COUNT_THREE(0.00)[4]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_HAM_SHORT(-0.47)[-0.472]; RCVD_IN_DNSWL_NONE(0.00)[209.85.160.178:from]; NEURAL_HAM_MEDIUM(-0.94)[-0.938]; FORGED_SENDER(0.30)[rlibby@freebsd.org,rlibby@gmail.com]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:15169, ipnet:209.85.128.0/17, country:US]; FROM_NEQ_ENVFROM(0.00)[rlibby@freebsd.org,rlibby@gmail.com]; FREEMAIL_ENVFROM(0.00)[gmail.com] X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 May 2020 06:59:04 -0000 On Wed, May 20, 2020 at 6:04 PM Rick Macklem wrote: > > Hi, > > Since I hadn't upgraded a kernel through the winter, it took me a while > to bisect this, but r358252 seems to be the culprit. > > If I do a kernel build over NFS using my not so big Pentium 4 (single core, > 1.25Gbytes RAM, i386), about every second attempt will hang. > When I do a "ps" in the debugger, I see processes sleeping on btalloc. > If I revert to r358251, I cannot reproduce this. > > Any ideas? > > I can easily test any change you might suggest to see if it fixes the > problem. > > If you want more debug info, let me know, since I can easily > reproduce it. > > Thanks, rick Nothing obvious to me. I can maybe try a repro on a VM... ddb ps, acttrace, alltrace, show all vmem, show page would be welcome. "btalloc" is "We're either out of address space or lost a fill race."