On 25 October 2013 01:39, John McIntosh <johnmci@smalltalkconsulting.com> wrote:
After you solve aioPoll()

You could consider waiting in the morphic polling loop until a VM UI event interrupt comes in, or to when you need to wake up to service your Morphic responsibilities. 

you always know when image wants to wake up - it is a delay semaphore.
basically , when image sets new Delay, it says to VM: wake me up at this moment.
This is i think the only thing, of course aside the async i/o & UI events.

I don't know how well different platforms support that,
but at least on windows, a following can be realized without the problem:

self primPleaseWakeMeUpWhenSomethingHappensButNotForNoReason

instead of:

[ self sleep:1000 "or wakeup if there something happens" ] repeat.

means, that OS Kernel can handle that and it halts CPU for your process until hardware interrupt arrives.

On Thu, Oct 24, 2013 at 7:34 PM, Igor Stasenko <siguctua@gmail.com> wrote:

On 25 October 2013 01:18, John McIntosh <johnmci@smalltalkconsulting.com> wrote:
Well let me reflect.
Nothing has changed, the VM energy sapping field is the same as  yesterday, just more evident. 

 I wasn't able to determine what code base is used, but if I go back 5 or 10 years.

(a) The morphic event polling cycle runs 50 times a second. One could write some timer consolidation code there to consider when do I have to wake up and paint all those morphs? No C/Objective-C/assembler/fortran required... 

(b) Maybe the VMs are event driven now and Morphic does not need to poll 50 times a second? 

(c) The BSD Unix socket system requires polling of some form.  But see work by Craig 10-15 back on "Flow"

(d) When all the Smalltalk Processes settle, the dispatcher runs the lowest priority task which calls relinquishProcessorForMicroseconds with a bogus value. 

(e) Cog uses heartbeat timer to interrupt interpreter at regular time periods
what can be done, i think it to suppress heartbeat, during relinquishProcessorForMicroseconds execution.
but that won't buy much, unless we increase the time period to sleep to be times larger than heartbeat cycle (both are 1ms).


sqInt ioRelinquishProcessorForMicroseconds(sqInt microSeconds) {
    //API Documented
    /* This operation is platform dependent.      */
    #pragma unused(microSeconds)

    sqInt       realTimeToWait,now,next;
    extern sqInt getNextWakeupTick(void);                //This is a VM Callback
    extern sqInt setInterruptCheckCounter(sqInt value);  //This is a VM Callback

    now = ioMSecs();
    next = getNextWakeupTick();
    /*BUG??? what if clock wraps? */
    if (next <= now)
        if (next == 0)
                realTimeToWait = 16;
            else {
                return 0;
            realTimeToWait = next - now;

    aioSleep((int) realTimeToWait*1000);
    return 0;

The real solution would be to not fall asleep,
but just put process into waitable state on 'wake up semaphore'
which then signaled if there's some i/o or timeout.

On Thu, Oct 24, 2013 at 6:21 PM, tim Rowledge <tim@rowledge.org> wrote:

Looking through some of the low-level changes in Mavericks I noticed stuff about timer consolidation. I *think* that it is something that you can offer to allow, rather than something done unto you code, but almost certainly it will have some sort of impact on the heartbeat ticker type of code used in stackvm/cog. Where is a skilled Mac vm maintainer when you need one?

tim Rowledge; tim@rowledge.org; http://www.rowledge.org/tim
"bOtHeR" said Pooh, mistaking the LSD tablet for aspirin

John M. McIntosh <johnmci@smalltalkconsulting.com>
Corporate Smalltalk Consulting Ltd. Twitter: squeaker68882

Best regards,
Igor Stasenko.

John M. McIntosh <johnmci@smalltalkconsulting.com>
Corporate Smalltalk Consulting Ltd. Twitter: squeaker68882

Best regards,
Igor Stasenko.