Hello,

Compile your shell and use the "--help" option. It will list all the options
available.
Note that more options are available in debug mode.

Regards,

Alexandre

On Sat, Apr 9, 2011 at 3:29 AM, Charles Lowell <[email protected]>wrote:

> Mads,
>
> That did help indeed. After invoking the gc() function, the callback
> was invoked as expected.
>
> Is there somewhere a comprehensive list of flags accepted by the VM?
> I've look around and find lots of them sprinkled about in test cases,
> wiki pages, and other documents, but nowhere a single list. Does such
> a beast exist?
>
> cheers,
> Charles
>
> On Apr 8, 2:28 pm, Mads Sig Ager <[email protected]> wrote:
> > Repeatedly calling IdleNotification in this way is not guaranteed to
> > force a garbage collection. If little has happened it will not. In
> > order to experiment with this you could use SetFlagsFromSting and pass
> > in --expose-gc. That will install a gc function in the global object
> > so you can force a gc by executing the js code "gc()".
> >
> > Hope this helps.
> >
> > -- Mads
> >
> >
> >
> >
> >
> >
> >
> > On Fri, Apr 8, 2011 at 9:20 PM, Charles Lowell <[email protected]>
> wrote:
> > > Anton,
> >
> > > I updated the snippet to try replicating your suggestion, but was
> > > still unable to get the WeakReferenceCallback to be invoked.
> >
> > >https://gist.github.com/908831
> >
> > > I would have expected the callback to have been invoked when GC is
> > > forced the first time after making the object handle weak. Is the
> > > Context is holding a strong reference to the object?
> >
> > > cheers,
> > > Charles
> >
> > > On Apr 8, 5:13 am, Anton Muhin <[email protected]> wrote:
> > >> Charles,
> >
> > >> Contexts have complicated lifetime.  If you just curious how weak
> > >> handles work, you'd better play with simpler objects.
> >
> > >> Handle goes near death state when it found out it references weakly
> > >> reachable object.  You're callback is never invoked as v8 retains the
> > >> context (it's a current context) and hence strongly reachable from
> > >> inside v8.  Value is base type, so everything is an instance of Value.
> >
> > >> Please note that you have a bug in your code: your weak callback must
> > >> either dispose the handle passed or revive it.
> >
> > >> And, just in case, most of objects are created and returned back in
> > >> Local handles.  Those handles live as long as handle scope to which
> > >> they belong and retain the object.  Thus the code:
> >
> > >> HandleScope hs;
> > >> Persistent p = Persistent::New(Object::New());
> > >> p.MakeWeak(...)
> > >> // Force GC
> >
> > >> will never trigger weak callback as l is alive and it retains the
> > >> object.  The right way:
> >
> > >> Persistent p;
> > >> {
> > >>   HandleScope hs;
> > >>   p = Persistent::New(Object::New());}
> >
> > >> p.MakeWeak(...)
> > >> // Force GC
> >
> > >> hth and yours,
> > >> anton.
> >
> > >> On Fri, Apr 8, 2011 at 1:59 AM, Charles Lowell <
> [email protected]> wrote:
> > >> > Hi,
> >
> > >> > I'm having trouble understanding when a Persistent handle is
> > >> > considered "Near Death", and when exactly a weak reference callback
> is
> > >> > invoked. Consider the following code:
> >
> > >> >https://gist.github.com/908831
> >
> > >> > It appears that the WeakReference Callback is never invoked.
> >
> > >> > I guess my questions are
> >
> > >> > 1) Why is it never considered near death? given that there is only
> one
> > >> > reference to it which is weak.
> >
> > >> > 2) why isn't the PrintlnWeakReferenceCallback ever invoked?
> >
> > >> > 3) WeakReferenceCallbacks take a Persistent<Value> as a parameter.
> > >> > What if, as in this case, the object is not a Value?
> >
> > >> > cheers,
> > >> > Charles
> >
> > >> > --
> > >> > v8-users mailing list
> > >> > [email protected]
> > >> >http://groups.google.com/group/v8-users
> >
> > > --
> > > v8-users mailing list
> > > [email protected]
> > >http://groups.google.com/group/v8-users
>
> --
> v8-users mailing list
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