On 08/01/2015 05:40 AM, Paolo Bonzini wrote:
On 31/07/2015 20:11, Jason J. Herne wrote:
Doh! Yep :). This problem is an artifact of moving the timer_mod from
cpu_throttle_thread into cpu_throttle_timer_tick. I'll have to go back
to the review comments and look at why that was done.
So, we made that change in v3 to eliminate the per cpu timer. With a per
cpu timer we avoid this problem and we no longer need to worry about
a throttle_thread_scheduled, and timers stacking. Paolo, you had originally
argued in favor of this change. With what we know now, do you still think
having only a single timer is best? Or should I switch back to a timer per
cpu? With a timer per cpu we can simply reset the timer immediately after
the sleep.
It's okay to have a single timer, only the formulas have to be
corrected: either you remove the pct/(1-pct) from the callback or you
add a /(1-pct) to the timer_mod.
Paolo
Paolo,
You are correct here. I've adjusted the timer formula and tested.
Everything seems to be playing nicely now. Sorry it took me a month to
get to this. I got pulled into some critical work and improved
auto-converge took a back seat. I know it is a pain to go back to
something you have not seen in a month so I appreciate any attention
this gets :). A new patch set will be inbound shortly...
--
-- Jason J. Herne (jjhe...@linux.vnet.ibm.com)
