Hi Jim,

Jim Cromie wrote:

some random sucesses ..

Ive been running an ipipe kernel as the default since shortly after 1/7.
Since then, Ive had a couple of freezes on boot,
and sometimes bash's auto-complete takes longer to complete,

Eh? Maybe the CONFIG_PCI_MSI syndrom again?

but other than that, things have been solid.

But that kernel wasnt configured using scripts/prepare-kernel.sh,
so was missing the xeno_* modules.


RTS|       -4814|       -4583|       -2582|       0|    00:02:00/00:02:00

This was run on a pentium-M laptop,
with cpu-clock running at 600 MHz, (capable of 1.7 GHz)
I presume this might explain the negative latancies.
Im aware this is un-supported ..

The negative values are just there because even at 600Mhz, the timing anticipation applied by the nucleus to compensate for the intrinsic latency of the box is too high; i.e. the nucleus performs a bit too well latency-wise, so the anticipated timer ticks end up being a bit early on schedule. IOW, all is fine. Given the figures above, you could probably reduce the anticipation factor by setting the CONFIG_XENO_HW_SCHED_LATENCY (Machine menu) parameter to, say, 2500 nanoseconds (the default null value tells the nucleus to use the pre-calibrated value, which might be higher than this for your setup).

Btw, I'm not sure if you enabled the local APIC in your kernel config; if you did not, you should: there is no reason to keep using the braindamage 8254 PIT when a LAPIC is available with your CPU.

The only thing that looks wrong is the test-duration.
I asked for 120 sec, it gave me 40 samples.
The test did take 120 to run.

You should disable the ACPI support if enabled, and especially everything related to the CPUfreq scaling and power suspend.



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