From owner-freebsd-ports@FreeBSD.ORG Sat Jan 8 11:00:18 2011 Return-Path: Delivered-To: freebsd-ports@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C38F710656D5 for ; Sat, 8 Jan 2011 11:00:18 +0000 (UTC) (envelope-from dennylin93@hs.ntnu.edu.tw) Received: from mail.hs.ntnu.edu.tw (mail.hs.ntnu.edu.tw [140.131.149.3]) by mx1.freebsd.org (Postfix) with ESMTP id 934288FC15 for ; Sat, 8 Jan 2011 11:00:18 +0000 (UTC) Received: by mail.hs.ntnu.edu.tw (Postfix, from userid 1001) id 98C874B7824; Sat, 8 Jan 2011 19:00:16 +0800 (CST) Date: Sat, 8 Jan 2011 19:00:16 +0800 From: Denny Lin To: Volodymyr Kostyrko Message-ID: <20110108110016.GA72486@mail.hs.ntnu.edu.tw> References: <20110102113714.GA81113@mail.hs.ntnu.edu.tw> <868vz34d76.fsf@gmail.com> <4D228490.9080602@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <4D228490.9080602@gmail.com> User-Agent: Mutt/1.4.2.3i Cc: Anonymous , freebsd-ports@freebsd.org Subject: Re: Ccache hangs while compiling and cache size is exaggerated X-BeenThere: freebsd-ports@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting software to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 08 Jan 2011 11:00:18 -0000 On Tue, Jan 04, 2011 at 04:23:12AM +0200, Volodymyr Kostyrko wrote: > 02.01.2011 16:01, Anonymous wrote: > >>I'm using ccache 3.1.3, and it often hangs while compiling. > > > >What its waiting channel? Hit ^T when it hangs or run under ktrace(1). This is what appears when I hit ^T: load: 0.96 cmd: ccache 25893 [zio->io_cv)] 3.83r 0.00u 0.06s 1% 1604k > Not just every compilation attempt triggers it. Chances are closer to 100/1. Correct, but it's always triggered at the same point. > >>Every time this happens, the cache size from $ ccache -s also becomes > >>ridiculously large (larger than the actual cache size). > >> > >>$ ccache -s > >>[...] > >>cache size 6.9 Gbytes > > > >>The filesystem says it's only 2.9 GB. > > > >How did you measure it? du(1) with `-A' option? > >For example, compression can make difference Compression is turned off. > I'd clarify this one. ccache reports size of cache +4G per damaged > subdir. If damaged subdir would be removed ccache reports normal size of > cache again. > > >>I can reproduce this, but I don't know what is causing this. > > This gives high IO. When ccache thinks cache is full it tries to purge > it, yet purge does nothing. But this means walking all subdir per each > compilation. This seems to be the exact reason ccache is hanging. Does anyone have a clue why subdirs are getting damaged and how this can be prevented? -- Denny Lin