From owner-freebsd-current@FreeBSD.ORG Mon Sep 20 10:27:25 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 60F7C1065670 for ; Mon, 20 Sep 2010 10:27:25 +0000 (UTC) (envelope-from mkhitrov@gmail.com) Received: from mail-vw0-f54.google.com (mail-vw0-f54.google.com [209.85.212.54]) by mx1.freebsd.org (Postfix) with ESMTP id 15A5B8FC1B for ; Mon, 20 Sep 2010 10:27:24 +0000 (UTC) Received: by vws2 with SMTP id 2so2024369vws.13 for ; Mon, 20 Sep 2010 03:27:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:mime-version:sender:received :in-reply-to:references:from:date:x-google-sender-auth:message-id :subject:to:cc:content-type; bh=PnvUy8/w30SBc2+hqgioVaM4LKb+X4V6Mso2LJpmJqc=; b=TwKFEzheq++WsCPGDPdlc4kguKG8siOZnPpRLq4ug1P+NrqZSywk86dFd44hrISLTh vJIZI4TDbIE19tHXPakF3KyNQiwa0u+uHXlWAuH+pmXIsuEBbWGBJ06mbqJUEObdpH78 aZsd+JUwmFzCF2La4uDVUwOLw9D3QbiY7sReo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:from:date :x-google-sender-auth:message-id:subject:to:cc:content-type; b=VSkMU9rGl2J4++HwFzGz3mQdINs2NNdQ91JVLtIzpoeBASVzFF/s6YpHFBzmWWROt2 3hcZUR8wsRJPXnp6f8QzqxDUlsbr9G+MUspUI7MHMwKoreOiT9Vsw+dcmrslSZbXousw jSAgRWhBugNDTEIiLQA1s6u9mNI8zo/oksS6s= Received: by 10.220.30.139 with SMTP id u11mr437413vcc.77.1284978444143; Mon, 20 Sep 2010 03:27:24 -0700 (PDT) MIME-Version: 1.0 Sender: mkhitrov@gmail.com Received: by 10.220.184.4 with HTTP; Mon, 20 Sep 2010 03:27:04 -0700 (PDT) In-Reply-To: References: <4C912926.6070409@FreeBSD.org> From: Maxim Khitrov Date: Mon, 20 Sep 2010 06:27:04 -0400 X-Google-Sender-Auth: D-JIyx5i9rxMOg7lh2B_c5hn3Yo Message-ID: To: Dmitry Krivenok Content-Type: text/plain; charset=UTF-8 Cc: freebsd-current@freebsd.org Subject: Re: buildworld + ccache trouble X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Mon, 20 Sep 2010 10:27:25 -0000 On Mon, Sep 20, 2010 at 4:43 AM, Dmitry Krivenok wrote: > Your patch works fine for me, thanks! > However, I don't see any performance gain when using ccache: > > Number of cache hits is very low. > I need to understand this... Make sure you have the following environment variables set: CCACHE_HASH_COMPILER=1 (2.4) CCACHE_COMPILERCHECK=content (3.0+) CCache will not use cached files if the compiler has changed. The default way of detecting this change is by comparing compiler's size and modification time. Since the modification time changes after each installworld, you are effectively clearing the cache for all subsequent compilations. Setting the above variables will cause the "sameness" of the compiler to be determined by hashing its contents, which should only change if the compiler code was actually modified. - Max