Date: Sat, 15 Sep 2001 17:23:07 -0500 From: mikea <mikea@mikea.ath.cx> To: stable@FreeBSD.ORG Subject: Re: make -j4 vs -j8... 4 works, but 8 does not Message-ID: <20010915172307.A73155@mikea.ath.cx> In-Reply-To: <p05101001b7c97cb4f801@[128.113.24.47]>; from drosih@rpi.edu on Sat, Sep 15, 2001 at 06:06:10PM -0400 References: <5.1.0.14.0.20010915123606.035fcc18@192.168.0.12> <p05101001b7c97cb4f801@[128.113.24.47]>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, Sep 15, 2001 at 06:06:10PM -0400, Garance A Drosihn wrote: > At 12:38 PM -0400 9/15/01, Mike Tancsa wrote: > >Should a parallel build always work ? I was just trying to stress > >a new series of MB we are evaluating and to my suprise, -j4 works, > >but not -j8 > > Well, in a philosophical sense, yes it "should" always work. Bugs > creep into the process from time-to-time. I can not say that I > know how to pin down such problems when they occur. I do know > that earlier this year I had some problem I was checking, and as > a tangent to that problem I did several fresh 'make buildworld's, > going from -j2 to -j10 on my dual 650-MHz pentium machine. I then > did md5 comparisons of the resulting obj-tree results, and they all > came out the same. Of course, I wasn't getting any errors at build > time, either. In my experience with a 2-CPU box, the problems with -j 5 or bigger are exclusively with module (or include file, etc.) A not being built by the time that process B needs it to complete a compile or link or whatever. These failures, in general, don't recur if the make is rerun from the failure point -- even with -j 8 or more. I frequently run with -j 16 when I'm doing kernel builds and buildworlds, and I haven't had any of those fail in a longish time. -- Mike Andrews mikea@mikea.ath.cx Tired old sysadmin since 1964 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20010915172307.A73155>