On 8 October 2013 22:03, Eliot Miranda <eliot.mira...@gmail.com> wrote:
> Hi Igor, > > > On Tue, Oct 8, 2013 at 2:27 AM, Igor Stasenko <siguc...@gmail.com> wrote: > >> >> >> >> On 7 October 2013 18:36, Norbert Hartl <norb...@hartl.name> wrote: >> >>> >>> Am 07.10.2013 um 16:36 schrieb Igor Stasenko <siguc...@gmail.com>: >>> >>> 1 thing. >>> >>> can you tell me what given expression yields for your VM/image: >>> >>> Smalltalk vm maxExternalSemaphores >>> >>> (if it gives you number less than 10000000 then i think i know what is >>> your problem :) >>> >>> It is 10000000 >>> >>> What would be the problem if it would be smaller? >>> >>> >> that just means your VM don't have external object size cap. >> I changed the implementation to not have hard limit (the arbitrary large >> number >> is there just to be "compatible" with previous implementation). >> > > If you've really done this why haven't you pushed changes back to me? You > think I like the limit ?!? ;-). But is your new implementation lock-free? > I went to some lengths to make sure that the Cog implementation is > thread-safe, by making signalling lock-free. But making it lock-free while > allowing growing was too much work. If your new implementation isn't > lock-free and/or isn't thread-safe then IMO the cure is worse than the > disease, because signals can get lost and that's much harder to diagnose > than deal with a limit that can only be set at startup. > > I understand your concerns. And inviting you to verify my implementation. It should be lock-free and thread-safe. All changes are in single file, so you can just take it and replace existing one.. https://github.com/pharo-project/pharo-vm/blob/master/platforms/Cross/vm/sqExternalSemaphores.c should be easy to pick up for you. > If you don't remember, in short, i changed the way to it works, by accumulating signals into static-sized buffer, which then flushed upon each interrupt. As long as time between two interrupts remain relatively small, it is highly improbable that this buffer will be overrun. -- Best regards, Igor Stasenko.
