Scott Cheloha <scottchel...@gmail.com> writes:
> On Tue, Jul 05, 2022 at 07:15:31AM -0400, Dave Voutila wrote: >> >> Scott Cheloha <scottchel...@gmail.com> writes: >> >> > [...] >> > >> > If you fail the test you will see something like this: >> > >> > tsc: cpu0/cpu2: sync test round 1/2 failed >> > tsc: cpu0/cpu2: cpu2: 13043 lags 438 cycles >> > >> > A printout like this would mean that the sync test for cpu2 failed. >> > In particular, cpu2's TSC trails cpu0's TSC by at least 438 cycles. >> > If this happens for *any* CPU we mark the TSC timecounter as >> > defective. >> >> I think this passes now on my dual-socket Xeon box? > > Yes, it passes. The timecounter on your machine should still have a > quality of 2000, i.e. we didn't mark it defective. > >> Full dmesg at the end of the email[1], but just the `tsc:' lines look >> like: >> >> $ grep tsc dmesg.txt >> tsc: cpu0: IA32_TSC_ADJUST: -5774382067215574 -> 0 >> tsc: cpu1: IA32_TSC_ADJUST: -5774382076335870 -> 0 >> tsc: cpu2: IA32_TSC_ADJUST: -5774382073829798 -> 0 >> tsc: cpu3: IA32_TSC_ADJUST: -5774382071913818 -> 0 >> tsc: cpu4: IA32_TSC_ADJUST: -5774382075956770 -> 0 >> tsc: cpu5: IA32_TSC_ADJUST: -5774382074583181 -> 0 >> tsc: cpu6: IA32_TSC_ADJUST: -5774382073199574 -> 0 >> tsc: cpu7: IA32_TSC_ADJUST: -5774382076500135 -> 0 >> tsc: cpu8: IA32_TSC_ADJUST: -5774382074705354 -> 0 >> tsc: cpu9: IA32_TSC_ADJUST: -5774382075954945 -> 0 >> tsc: cpu10: IA32_TSC_ADJUST: -5774382070567294 -> 0 >> tsc: cpu11: IA32_TSC_ADJUST: -5774382075968443 -> 0 >> tsc: cpu12: IA32_TSC_ADJUST: -5774382067353478 -> 0 >> tsc: cpu13: IA32_TSC_ADJUST: -5774382071926523 -> 0 >> tsc: cpu14: IA32_TSC_ADJUST: -5774382074619890 -> 0 >> tsc: cpu15: IA32_TSC_ADJUST: -5774382070107058 -> 0 >> tsc: cpu16: IA32_TSC_ADJUST: -5774382076196640 -> 0 >> tsc: cpu17: IA32_TSC_ADJUST: -5774382075090665 -> 0 >> tsc: cpu18: IA32_TSC_ADJUST: -5774382073529646 -> 0 >> tsc: cpu19: IA32_TSC_ADJUST: -5774382076443616 -> 0 >> tsc: cpu20: IA32_TSC_ADJUST: -5774382074994536 -> 0 >> tsc: cpu21: IA32_TSC_ADJUST: -5774382076309520 -> 0 >> tsc: cpu22: IA32_TSC_ADJUST: -5774382070947686 -> 0 >> tsc: cpu23: IA32_TSC_ADJUST: -5774382073056320 -> 0 > > Fascinating. Wonder what the heck it's doing down there. > >> It does look like there's a newer BIOS version for this machine, so I'll >> try updating it later today and repeating the test to see if anything >> changes. After a BIOS update, still similar output. "new" bios: bios0 at mainbus0: SMBIOS rev. 2.8 @ 0xec0f0 (105 entries) bios0: vendor Dell Inc. version "A34" date 10/19/2020 bios0: Dell Inc. Precision Tower 7810 $ dmesg | grep tsc tsc: cpu0: IA32_TSC_ADJUST: -4070378216 -> 0 tsc: cpu1: IA32_TSC_ADJUST: -4081094631 -> 0 tsc: cpu2: IA32_TSC_ADJUST: -4078853396 -> 0 tsc: cpu3: IA32_TSC_ADJUST: -4074362824 -> 0 tsc: cpu4: IA32_TSC_ADJUST: -4080872645 -> 0 tsc: cpu5: IA32_TSC_ADJUST: -4075673830 -> 0 tsc: cpu6: IA32_TSC_ADJUST: -4081906959 -> 0 tsc: cpu7: IA32_TSC_ADJUST: -4073006269 -> 0 tsc: cpu8: IA32_TSC_ADJUST: -4081803214 -> 0 tsc: cpu9: IA32_TSC_ADJUST: -4081294540 -> 0 tsc: cpu10: IA32_TSC_ADJUST: -4079817920 -> 0 tsc: cpu11: IA32_TSC_ADJUST: -4079871039 -> 0 tsc: cpu12: IA32_TSC_ADJUST: -4070522580 -> 0 tsc: cpu13: IA32_TSC_ADJUST: -4077205405 -> 0 tsc: cpu14: IA32_TSC_ADJUST: -4081797309 -> 0 tsc: cpu15: IA32_TSC_ADJUST: -4078574630 -> 0 tsc: cpu16: IA32_TSC_ADJUST: -4081539272 -> 0 tsc: cpu17: IA32_TSC_ADJUST: -4079657247 -> 0 tsc: cpu18: IA32_TSC_ADJUST: -4080469326 -> 0 tsc: cpu19: IA32_TSC_ADJUST: -4073404194 -> 0 tsc: cpu20: IA32_TSC_ADJUST: -4081473720 -> 0 tsc: cpu21: IA32_TSC_ADJUST: -4076195877 -> 0 tsc: cpu22: IA32_TSC_ADJUST: -4077876814 -> 0 tsc: cpu23: IA32_TSC_ADJUST: -4081863303 -> 0 And still a quality tsc :) : $ sysctl kern.timecounter kern.timecounter.tick=1 kern.timecounter.timestepwarnings=0 kern.timecounter.hardware=tsc kern.timecounter.choice=i8254(0) acpihpet0(1000) tsc(2000) acpitimer0(1000) -dv
