[squeak-dev] [ANN] TruffleSqueak 20.1.0 released

Fabio Niephaus lists at fniephaus.com
Sun Jun 21 20:24:01 UTC 2020

On Sun, Jun 21, 2020 at 9:24 PM Stéphane Rollandin
<lecteur at zogotounga.net> wrote:
> Le 21/06/2020 à 20:18, Fabio Niephaus a écrit :
> > Hi Stef,
> >
> > Sorry about that. I'm afraid I don't have access to a native Windows
> > machine at the moment, but I'll try to have a look at it. Does the CPU
> > usage drop after a couple of minutes? And is the UI more responsive
> > after that?
> Here is the behavior as far as I can see: at startup, uses up to 30% of
> my overall CPU, then stabilize at 25% (that's two cores at 100%). Then
> it calms down to a couple %, but jumps back at 25% at every action in
> the Squeak image, even seemingly innocuous one, such as opening a
> browser, clicking in a workspace, etc.. All these take time (a browser
> takes about 2 seconds to open)

It shouldn't stabilize with two cores at 100%, something might be off.
If you have some time, maybe run VisualVM [1] (ships with GraalVM) and
see what's causing the load. I'm happy to help if you have any

Nonetheless, there will always be some inefficiencies compared with
OpenSmalltalkVM. For example, we don't have direct access to and
control over the Java GC, so it's quite hard to make allInstances very
fast. That's also the reason why some tools open with a slight delay.
But then again, warmup is quite bad and it's expected that when you do
new things, the JIT needs some time to make it fast. A demo of
TruffleSqueak and OSVM running the BouncingAtomsMorph side-by-side is
at [2].


[1] https://visualvm.github.io
[2] https://twitter.com/fniephaus/status/1021366253045387265

> Tested over the course of 20 minutes; I cannot do this for too long
> because my laptop heats up very fast in those conditions, unfortunately.
> Best,
> Stef

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