From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kip Macy Subject: Re: FreeBSD/Xen ugliness Date: Sat, 8 Jan 2005 21:05:07 -0800 (PST) Message-ID: <20050108210000.B8527@demos.bsdclusters.com> References: <41DD8E03.600@dsdk12.net> <20050106111730.N11243@demos.bsdclusters.com> <41DD9C39.7070203@dsdk12.net> <20050106121932.F24878@demos.bsdclusters.com> <41E09F7A.4050604@dsdk12.net> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <41E09F7A.4050604@dsdk12.net> Sender: xen-devel-admin@lists.sourceforge.net Errors-To: xen-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Derrik Pates Cc: xen-devel@lists.sourceforge.net List-Id: xen-devel@lists.xenproject.org I've seen the same timing issues. We do call yield where appropriate: static void cpu_idle_default(void) { #if 0 /* * we must absolutely guarentee that hlt is the * absolute next instruction after sti or we * introduce a timing window. */ __asm __volatile("sti; hlt"); #endif enable_intr(); HYPERVISOR_yield(); } So I'm not sure what the problem is. After the 5.3 work and coredump is done I might look into it. There may have been some fixes to the clock code in the meantime. -Kip On Sat, 8 Jan 2005, Derrik Pates wrote: > Kip: > > Well, I have good news; thanks to Darren Tucker pointing out that the > boot.netif.* parameters _have_ to be added, I was able to successfully > boot your FreeBSD/Xen kernel. It seems to work okay so far. It fairly > regularly (every few minutes or so) spits out a line like: > > Expensive timeout(9) function: 0xc00b0bd0(0) 0.010000854 s > > at me, but it seems to otherwise behave as FreeBSD should. The only > thing I've noticed so far is that, looking at the output of 'xm list', > its domain's virtual-time clock seems to grow at a constant rate. I'm > guessing this means it doesn't call up to the hypervisor and say "Please > schedule someone else, I'm idle right now" when it has nothing to do. It > doesn't seem to affect the performance of other domains though, but I > thought it worth pointing out. Unfortunately, I don't know enough about > FreeBSD's scheduler to make the necessary changes to make this work as > it should. I'll have to see about getting a proper full CVS pull of the > sys/ tree for 5.2.1 on my FreeBSD install in VMware, and see if I can > make a FreeBSD kernel build work; however, I'd like to see the 5.3 > kernel when you get around to it. > > -- > Derrik Pates > dpates@dsdk12.net > ------------------------------------------------------- The SF.Net email is sponsored by: Beat the post-holiday blues Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek. It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt