[Vm-dev] Re: [Pharo-project] newDelta >0 failed in sqUnixMemory
John M McIntosh
johnmci at smalltalkconsulting.com
Fri Jan 30 20:09:04 UTC 2009
mmm, let me clarify. I currently use Apple's GCC 4.0.1 <i686-apple-
darwin9-gcc-4.0.1>
that works fine for macintel, 3.3 is required for decent performance
on powerpc.
The version that I worked with Michael on was the LLVM GCC 4.2 and or
GCC 4.2. Michael I believe tried GCC 4.3
Michael said:
"after managing to build the VM with the recommended setup I tried
with newer GCCs (3.45 and 4.3), both significantly slower.
GCC 3.45 about 50%, GCC 4.3 about 80% of GCC 2.95."
With 4.0.1 the compiler optimizations tweaks in the macintosh carbon
VM build give it a good 10%? better than the defaults optimizations.
However that presupposes -mtune=prescott -march=pentium-m which one
can get away with on the macintosh platform, versus the
bazillion cpu choices & clones on the Wintel side.
On 30-Jan-09, at 9:37 AM, Andreas Raab wrote:
> John M McIntosh wrote:
>> Yes, I can't recall it was what 50% of the performance of a 3.x
>> compile out of the box, and after *much*
>> tweaking of compiler flags it was mmm just 20% slower.. Well
>> certainly the performance impact was measured in 10 of percent.
>
> So what do you use today? gcc 4? And how does it stack up
> performance-wise against a Windows VM on the same box? I personally
> wouldn't mind moving forward but the results in the past were so
> godawful that I haven't tried in a long time.
>
> Cheers,
> - Andreas
>
>> On 30-Jan-09, at 4:33 AM, Michael Rueger wrote:
>>>
>>> John McIntosh and I actually spent some time a few ago compiling
>>> VMs on
>>> Windows and MacOS with the newest GCCs and ran into a bunch of
>>> problems,
>>> especially concerning performance. I had to put the work on the back
>>> burner for now, but switching to newer compilers will take a bit of
>>> extra work at some point.
>>>
>>> Michael
>> --
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>> John M. McIntosh <johnmci at smalltalkconsulting.com>
>> Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com
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John M. McIntosh <johnmci at smalltalkconsulting.com>
Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com
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