From owner-freebsd-net@FreeBSD.ORG Tue Dec 27 19:25:57 2011 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3E57E1065670 for ; Tue, 27 Dec 2011 19:25:57 +0000 (UTC) (envelope-from ml@my.gd) Received: from mail-ww0-f50.google.com (mail-ww0-f50.google.com [74.125.82.50]) by mx1.freebsd.org (Postfix) with ESMTP id C44D68FC13 for ; Tue, 27 Dec 2011 19:25:56 +0000 (UTC) Received: by wgbdr11 with SMTP id dr11so21330900wgb.31 for ; Tue, 27 Dec 2011 11:25:55 -0800 (PST) Received: by 10.227.204.208 with SMTP id fn16mr28890322wbb.6.1325013955812; Tue, 27 Dec 2011 11:25:55 -0800 (PST) Received: from dfleuriot-at-hi-media.com ([83.167.62.196]) by mx.google.com with ESMTPS id fg15sm29128063wbb.7.2011.12.27.11.25.54 (version=SSLv3 cipher=OTHER); Tue, 27 Dec 2011 11:25:55 -0800 (PST) Message-ID: <4EFA1BC1.5060605@my.gd> Date: Tue, 27 Dec 2011 20:25:53 +0100 From: Damien Fleuriot User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:8.0) Gecko/20111105 Thunderbird/8.0 MIME-Version: 1.0 To: Warren Block References: <4EF9E2D6.7050705@my.gd> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-net@freebsd.org Subject: Re: Compiling only "network" part of the kernel X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Dec 2011 19:25:57 -0000 On 12/27/11 8:19 PM, Warren Block wrote: > On Tue, 27 Dec 2011, Damien Fleuriot wrote: >> On 12/27/11 3:51 PM, Warren Block wrote: >>> On Tue, 27 Dec 2011, Rajneesh Kumar wrote: >>> >>>> During my development, I want to check if my modules compile >>>> successfully >>>> or not. I am only changing the ARP portion and whenever I compile my >>>> kernel, it takes around 20mins and compiles all different modules also. >>>> I just want to compile and check whether my ARP modules, which I have >>>> changed, compile fine or not. How to do it? >>> >>> Others have mentioned ways to reduce what is rebuilt. devel/ccache can >>> be used in combination with those. Even by itself it ought to seriously >>> reduce kernel compile time. >> >> Would ccache also help with world/ports compile times ? > > Yes, if some of it is already in the cache. Ports change relatively > rarely, so I don't use ccache for them. > >> Are there any drawbacks to using it ? (the underlying question being: is >> it worthy of a production environment ?) > > It needs cache space and probably slows things down a bit when code is > not already in the cache. Some source updates invalidate a lot of the > cache. But no other problems I've noticed. > > Times for 8-STABLE on an E8400 CPU, everything in the cache. > > make -j4 buildworld: > Normal 19:41 > ccache 6:02 > > make -j4 buildkernel (custom kernel): > Normal 8:43 > ccache 2:47 > > Those are best-case times. A typical ccache buildworld after csup to > -stable is about 9 minutes on this system. That sounds good enough. Are there any performance hits during production, as in, when not busy rebuilding the world or whatever, just normal daily operation ?