Date: Wed, 28 Mar 2007 15:26:24 +0100 From: Rui Paulo <rpaulo@gmail.com> To: freebsd-i386@freebsd.org Subject: Re: Timecounting issue Message-ID: <460A7B10.7080404@gmail.com> In-Reply-To: <e1309ba60703280457v394e7263x17f0e93512d11ad4@mail.gmail.com> References: <e1309ba60703280457v394e7263x17f0e93512d11ad4@mail.gmail.com>
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Rui Paulo wrote: > Hi, > I have a machine only knows to count time if I'm using TSC. > > For example: > # sysctl kern.timecounter.hardware=ACPI-fast && time sleep 1 && sysctl > kern.timecounter.hardware=i8254 && time sleep 1 && sysctl > kern.timecounter.hardware=HPET && time sleep 1 && sysctl > kern.timecounter.hardware=TSC && time sleep 1 > > Gives: > kern.timecounter.hardware: HPET -> ACPI-fast > sleep 1 0.00s user 0.00s system 0% cpu 1.517 total > kern.timecounter.hardware: ACPI-fast -> i8254 > sleep 1 0.00s user 0.00s system 0% cpu 1.516 total > kern.timecounter.hardware: i8254 -> HPET > sleep 1 0.00s user 0.00s system 0% cpu 1.516 total > kern.timecounter.hardware: HPET -> TSC > sleep 1 0.00s user 0.00s system 0% cpu 1.006 total > > This happens if I enable SMP or not. > > Any hint on how to debug this ? I found the problem. My machine only works correctly with HZ=100. -- Rui Paulo | PGP: F0E4 C7C7 1653 79B7 78DC DD73 64FA B2C6 CF45 1F84
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