Date: Fri, 24 Jun 2005 18:50:02 +0200 From: Jens Schweikhardt <schweikh@schweikhardt.net> To: John Baldwin <jhb@FreeBSD.org> Cc: freebsd-current@FreeBSD.org Subject: Re: Timekeeping hosed by factor 3, high lapic[01] interrupt rates Message-ID: <20050624165002.GA860@schweikhardt.net> In-Reply-To: <200506231714.40891.jhb@FreeBSD.org> References: <20050516113420.GA786@schweikhardt.net> <200506221057.48595.jhb@FreeBSD.org> <20050623205854.GA763@schweikhardt.net> <200506231714.40891.jhb@FreeBSD.org>
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On Thu, Jun 23, 2005 at 05:14:39PM -0400, John Baldwin wrote: ... # Ok. What timecounter does your UP kernel use, and does your UP kernel break # if you change the timecounter to i8254? The UP uses the TSC: $ sysctl -a|grep timec kern.timecounter.stepwarnings: 0 kern.timecounter.nbinuptime: 136311 kern.timecounter.nnanouptime: 0 kern.timecounter.nmicrouptime: 664 kern.timecounter.nbintime: 1273 kern.timecounter.nnanotime: 36 kern.timecounter.nmicrotime: 1237 kern.timecounter.ngetbinuptime: 405 kern.timecounter.ngetnanouptime: 29 kern.timecounter.ngetmicrouptime: 2534 kern.timecounter.ngetbintime: 0 kern.timecounter.ngetnanotime: 0 kern.timecounter.ngetmicrotime: 5 kern.timecounter.nsetclock: 2 kern.timecounter.hardware: TSC kern.timecounter.choice: TSC(800) i8254(0) dummy(-1000000) kern.timecounter.tick: 1 kern.timecounter.smp_tsc: 0 When I do $ sysctl kern.timecounter.hardware=i8254 on the UP the time dilation by factor 3 starts and the lapic rate increases. So yes, that breaks the UP kernel. Regards, Jens -- Jens Schweikhardt http://www.schweikhardt.net/ SIGSIG -- signature too long (core dumped)
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