I treid make -j 30 build{world,kernel} (latest -CURRENT) on 24-core machine and
see poor
scalability of pmap/mtx -- more then 50% cpu spend on system time.
pmcstat:
@ CPU_CLK_UNHALTED_CORE [194841 samples]
42.65% [83102]_mtx_lock_sleep @ /boot/kernel/kernel
40.97% [34051] pmap_enter
Known problem. There is an open disagreement about how to improve the
granularity of locking in pmap.
-Kip
On Tue, Apr 24, 2012 at 9:14 PM, Slawa Olhovchenkov s...@zxy.spb.ru wrote:
I treid make -j 30 build{world,kernel} (latest -CURRENT) on 24-core machine
and see poor
scalability of
On Tue, Apr 24, 2012 at 09:27:30PM +0200, K. Macy wrote:
Known problem. There is an open disagreement about how to improve the
granularity of locking in pmap.
split locking to process-specific information and global information?
use lock-free lists (i see TAILQ_INSERT_TAIL in pmap_enter)?
No. I developed a patch from Jeffr that pushed the vm_page_lock array
down in to the machine dependent code, replacing most of the uses of
the single vm_page_queue_lock. However, alc doesn't like the design
and has not proposed an alternative.
-Kip
On Tue, Apr 24, 2012 at 10:36 PM, Slawa
On Tue, Apr 24, 2012 at 10:43:08PM +0200, K. Macy wrote:
No. I developed a patch from Jeffr that pushed the vm_page_lock array
down in to the machine dependent code, replacing most of the uses of
the single vm_page_queue_lock. However, alc doesn't like the design
and has not proposed an
It's a bit dated at this point. Nonetheless, when gitorious is able to
give something other than 503 to my search queries I'll post it.
On Tue, Apr 24, 2012 at 10:45 PM, Slawa Olhovchenkov s...@zxy.spb.ru wrote:
On Tue, Apr 24, 2012 at 10:43:08PM +0200, K. Macy wrote:
No. I developed a patch
You can try these. Your mileage *will* vary.
https://gitorious.org/~kmm/freebsd/kmm-sandbox/commits/work/svn_release_8_1_0_page_lock
https://gitorious.org/~kmm/freebsd/kmm-sandbox/commits/work/svn_trunk_page_lock
On Tue, Apr 24, 2012 at 10:51 PM, K. Macy km...@freebsd.org wrote:
It's a bit
