freebsd stable - Sep 2005 - HEADS UP! Debugging, SMP changed in RELENG_6

All,

I've turned off kernel deubgging (INVARIANTS, WITNESS, KDB) and malloc
debugging (the default is now 'aj) in the RELENG_6 branch in preparation
for 6.0-BETA5.  I've also turned off SMP in the i386 and amd64 GENERIC
kernels and have added and SMP kernel config for those architectures.
All of these changes are nearly identical to what is in RELENG_5.  All
of this was done to facilitate performance measurement of the upcoming
release and to recognize that our buglist is shrinking considerably and
thus the release will be coming soon.

### IMPORTANT ###

If you are using a stock GENERIC kernel on amd64 or i386 and expect
multiple CPUs to be enabled, you must either switch to the SMP kernel
config, or add the 'options SMP' line back to the GENERIC config.
Multiple CPUs, including mutli-core and Hyperthreading, will only be
enabled when this option is included.  Hyperthreading also requires
that you add the line 'machdep.hyperthreading_allowed=1' to
/boot/loader.conf.

Given the growth of multicore offerings from AMD and Intel, the default
on SMP may change in future releases as SMP systems become ubiquitous.
Appropriate warning will be given on the mailing lists if this happens.

Scott

On Saturday 17 September 2005 21:00, Scott Long wrote:
> All,
>
> I've turned off kernel deubgging (INVARIANTS, WITNESS, KDB) and malloc
> debugging (the default is now 'aj) in the RELENG_6 branch in
preparation
> for 6.0-BETA5.  I've also turned off SMP in the i386 and amd64 GENERIC
> kernels and have added and SMP kernel config for those architectures.
> All of these changes are nearly identical to what is in RELENG_5.  All
> of this was done to facilitate performance measurement of the upcoming
> release and to recognize that our buglist is shrinking considerably and
> thus the release will be coming soon.
>
> ### IMPORTANT ###
>
> If you are using a stock GENERIC kernel on amd64 or i386 and expect
> multiple CPUs to be enabled, you must either switch to the SMP kernel
> config, or add the 'options SMP' line back to the GENERIC config.
> Multiple CPUs, including mutli-core and Hyperthreading, will only be
> enabled when this option is included.  Hyperthreading also requires
> that you add the line 'machdep.hyperthreading_allowed=1' to
> /boot/loader.conf.
>
> Given the growth of multicore offerings from AMD and Intel, the default
> on SMP may change in future releases as SMP systems become ubiquitous.
> Appropriate warning will be given on the mailing lists if this happens.
>
> Scott

I've just spent the past few days trying to get 6.0 to work with my SATA
drives with little results.  Here is a DMESG when I booit with 5.4:

ad0: 6149MB <WDC AC26400B/32.02S32> [13328/15/63] at ata0-master UDMA33
acd0: CDRW <TEAC DVD+RW DV-W58E/D.0J> at ata1-master UDMA33
ad4: 76319MB <WDC WD800JD-00HKA0/13.03G13> [155061/16/63] at ata2-master 
SATA150
ad6: 114473MB <WDC WD1200JD-00HBB0/08.02D08> [232581/16/63] at ata3-master
SATA150

The drives work fine in 5.4, but with 6.0 ad4 errors out, you can see it with 
atacontrol but it can't be reinitialized and there is only /dev/ad4 but none
of the slices. ad6 works ok during reads but anything more than very light
writing and the system reboots.  Given these drives work with 5.4 it seems
a little more work needs to go into 6.0 before doing new releases I would
hope.

-Mike