Hi Stef,

here is the script I use:

| c1 c2 c3 n1 n2 n3 l1 l2 l3 |
c1 := c2 := c3 := 0.
n1 := (Announcer>>#announce:) ast.
n2 := #(subscribe:do: subscribe:send:to: basicSubscribe:) collect: [ :e | (Announcer>>e) ast ].
n3 := #(unsubscribe: removeSubscription:) collect: [ :e | (Announcer>>e) ast ].
l1 := MetaLink new metaObject: [ c1 := c1 + 1 ]; selector: #value.
l2 := MetaLink new metaObject: [ c2 := c2 + 1 ]; selector: #value.
l3 := MetaLink new metaObject: [ c3 := c3 + 1 ]; selector: #value.
[ n1 link: l1. n2 do: [ :e | e link: l2 ]. n3 do: [ :e | e link: l3 ].
(Duration minutes: 1) wait.
n1 removeLink: l1. n2 do: [ :e | e removeLink: l2 ]. n3 do: [ :e | e removeLink: l3 ].
{ 'announce' -> c1. 'subscribe' -> c2.�� 'unsubscribe' -> c3 } inspect ] forkAt: Processor userBackgroundPriority

Images int��gr��es 1

2016-09-01 9:28 GMT+02:00 Thierry Goubier <thierry.goubier@gmail.com>:

Hi Stef,

2016-09-01 8:13 GMT+02:00 stepharo <stepharo@free.fr>:
Hi thierry

I think that if we would have a tool to show us the activity I'm quite sure that we would find bugs

or mistaken behavior.

Yes. I did some checks on Morphic and AltBrowser after getting the numbers, to see if I wasn't
doing something wrong with my code.

could you send the scripts you did?

Later today. I don't have access now to the laptop where I did it.

Thierry
��

Stef

Le 30/8/16 �� 22:36, Thierry Goubier a ��crit :

Numbers for the discussion:

No activity, empty desktop:
announcements�� 608/minute
subscribe add/remove�� 9/minute

Activity, AltBrowser:
announcements�� 1109/minute
subscribe add/remove�� 207/minute

Activity, Nautilus:
announcements�� 2488/minute
subscribe add/remove�� 716/minute

Empirically the same processus in both environments: open two system browser, in one, find the Announcer class, browse through a few of the methods, select basicSubscribe: and ask for senders.

Tracing done with Metalinks during one minute.

Not exactly what I would have expected, especially the ratio subscribe add/remove and announcements.

Thierry

Le 30/08/2016 �� 17:36, Henrik Johansen a ��crit :

On 30 Aug 2016, at 5:16 , Thierry Goubier
<thierry.goubier@gmail.com> wrote:

I have the same concern with an Announcer optimized for certain use
cases, in the fact that the announcer creator is the one choosing
the 'kind of' optimisation it would target, hoping that the
listeners will conform to that use case...

There simply is no silver bullet that will give unbeatable
performance in all scenarios; and focusing on improving one facet of
the default implementation will inevitably lead to either - the loss
of some important property (general thread-safety if removing the
mutex protection, ability to unsubscribe in handler if removing the
copy operation and extending the delivery mutex protection, etc.) -
greatly degenerated performance for another facet (like #remove for
OC's).

That said, the current implementation is very geared towards decent,
balanced subscribe/unsubscribe performance, at the expense of
delivery speed. I've said it before, and still think, that offering
at least one other implementation emphasizing delivery speed over
subscription/unsubscription performance, in the same way the original
implementation did (and/or changing the default Announcer to switch
between the two dynamically based on heuristics) *would* be a
valuable addition to the general library.

Cheers, Henry