Anders wrote: > Avi Kivity wrote: > > >> if select() doesn't enable signals (like you can do with pselect) you >> may sit for a long time in select() until the timer expires. >> > > Hm. Does the guest timer affect host userspace in all configurations? The > original trigger for my SIGIO patch was that opening a VNC connection > would take up to a second, until the qemu RTC timer fired. > >
Right, if the guest is using the lapic or pit timers, there is no periodic signal to userspace. > >> Consider a 100Hz Linux guest running 'ls -lR' out of a cold cache: >> instead of 1-2 ms disk latencies you'll see 10 ms latencies, killing >> performance by a factor of 5. >> > > I guess this works out even worse for a dyntick guest? > > > Yes. We can't depend on guest activity for correctness. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
