[Vm-dev] RoarVM: The Manycore SqueakVM
siguctua at gmail.com
Sat Nov 6 16:01:43 UTC 2010
On 6 November 2010 17:26, Levente Uzonyi <leves at elte.hu> wrote:
> On Thu, 4 Nov 2010, Stefan Marr wrote:
>> Hi Bert:
>> On 04 Nov 2010, at 20:20, Bert Freudenberg wrote:
>>>>> So RoarVM is about 4 times slower in sends, even more so for bytecodes.
>>>>> It needs 8 cores to be faster the regular interpreter on a single core. To
>>>>> the good news is that it can beat the old interpreter :) But why is it so
>>>>> much slower than the normal interpreter?
>>>> Well, one the one hand, we don't use stuff like the GCC label-as-value
>>>> extension to have threaded-interpretation, which should help quite a bit.
>>>> Then, the current implementation based on pthreads is quite a bit slower
>>>> then our version which uses plain Unix processes.
>>>> The GC is really not state of the art.
>>>> And all that adds up rather quickly I suppose...
>>> Hmm, that doesn't sound like it should make it 4x slower ...
>> Do you know some numbers for the switch/case-based vs. the threaded
>> version on the standard VM?
>> How much do you typically gain by it?
> If threaded means gnuified (jump table instead of the linear search), then
> it gives ~2x speedup for the standard SqueakVM.
to my own experience it gives 30%
Igor Stasenko AKA sig.
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