From owner-svn-src-head@freebsd.org Sat Nov 7 03:59:26 2015 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 529AFA27F0A; Sat, 7 Nov 2015 03:59:26 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-ig0-x235.google.com (mail-ig0-x235.google.com [IPv6:2607:f8b0:4001:c05::235]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 2D3BA192C; Sat, 7 Nov 2015 03:59:26 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: by igbhv6 with SMTP id hv6so47929098igb.0; Fri, 06 Nov 2015 19:59:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=dgExjZvIKMPp+Y9MpK//xXXaqb9Hxrv6oY/v6VWEYUk=; b=yZ0ouLvVzFksaxF5GJ7JjS7Xsys2zuqrlb+EtNXLMsffKKcd7woyEq9xSeQWPGmMMs 5YFUcgBf8Tc3ovQtVQHDCWCFh0pWwtJw+UHKSN8mJky9//w24Cfu+R7+h17VIA1ek1q3 NAa9d9Yjq+55mCUHufcNIkyZd0Y2GgrfiWOmzr8SKv/WFFlqGRFZRlFVXuBc5gRCnCHI 7NQ6U9fvh46E5a8JHO6xkDX+xo+hxmCQzZt0vlt7DDWSJYSQI3fQoEBDaEJRDO4bNPFk Eqn7ou8KTZ4vhB5ge41VGtKa3UrNj3eKwpBjPh4CyHwreqOkGe4MCJtH2H6ZmYYcTLli f0CA== MIME-Version: 1.0 X-Received: by 10.50.155.41 with SMTP id vt9mr11588024igb.22.1446868765595; Fri, 06 Nov 2015 19:59:25 -0800 (PST) Received: by 10.36.217.196 with HTTP; Fri, 6 Nov 2015 19:59:25 -0800 (PST) In-Reply-To: References: <201510140210.t9E2A79H056595@repo.freebsd.org> <20151029212554.799f76eb@kalimero.tijl.coosemans.org> Date: Fri, 6 Nov 2015 19:59:25 -0800 Message-ID: Subject: Re: svn commit: r289279 - in head/sys: kern vm From: Adrian Chadd To: Tijl Coosemans Cc: Jeff Roberson , "src-committers@freebsd.org" , "svn-src-all@freebsd.org" , "svn-src-head@freebsd.org" , Konstantin Belousov Content-Type: text/plain; charset=UTF-8 X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 07 Nov 2015 03:59:26 -0000 hiya, Just bringing this to peoples attention again - the same issue (buf exhaustion, stuck in a loop trying to wake things up) exists. I'm going to commit the sched_yield() change with a big comment about why it's here and that it needs further investigation. That way things are stable again enough to use whilst this gets debugged. Thanks! -adrian On 4 November 2015 at 12:43, Adrian Chadd wrote: > HI, > > FYI - this patch did fix my initial issue, but further work in > multi-user mode caused it to still hang. I haven't diagnosed it yet; I > just put back the yield call so bufdaemon could run. > > So yeah, we still have some work to do. It hit the same problem; stuck > in a loop calling the path to wakeup bufdaemon, but then not sleeping > on anything. > > > > -adrian > > > On 2 November 2015 at 14:13, Adrian Chadd wrote: >> Hi Tijl, and others; >> >> Here's something that Jeff came up with that fixes my problem: >> >> adrian@victoria:~/work/freebsd/head-embedded/src % svn diff sys/kern/ >> Index: sys/kern/vfs_bio.c >> =================================================================== >> --- sys/kern/vfs_bio.c (revision 290048) >> +++ sys/kern/vfs_bio.c (working copy) >> @@ -2910,7 +2910,7 @@ >> } while(buf_scan(false) == 0); >> >> if (reserved) >> - bufspace_release(maxsize); >> + atomic_subtract_long(&bufspace, maxsize); >> if (bp != NULL) { >> bp->b_flags |= B_INVAL; >> brelse(bp); >> >> >> Would you/others please try this and see if it improves things? It >> improves things for me on these memory-starved MIPS boards. >> >> >> >> -a