Bill Holler wrote: > How often will callouts cause a cross-call to another cpu? > Will this be eliminated with the new per-cpu callout infrastructure? > > Callouts, by themselves, don't use X-calls. However, normal callouts are handled via taskq threads. So, waking up a taskq thread will involve the customary preemption actions which will involve X-calls. Also, realtime callouts are typically used to wake up threads. This wake up can involve the same kind of X-calls. There isn't a whole lot we can do about it.
I haven't yet had a chance to study how the new design reduces X-calls although the per-CPU nature of things suggests there may be less X-calling. However, I have no data on that. > Eric noticed callouts causing cross-calls make it more difficult > for the idle thread to predict how long it will be idle. > > Bill > _______________________________________________ > tesla-dev mailing list > tesla-dev at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/tesla-dev >
