Are you talking about the incremental GC 
<https://github.com/JuliaLang/julia/pull/5227>?

It happens that, since I'm making some experiments with a (pseudo-)realtime 
simulation with Julia, I also have that branch compiled.
In my realtime experiment, at the activation of a Timer with a period of 
2.2ms, I get a big delay of  +/-9ms each +/-1sec. when using master Julia.
By using the incremental GC those delays disappear.

However, in the time measurements I described before, the use of 
the incremental GC doesn't seem to produce any better results...
 
On Tuesday, June 17, 2014 5:32:34 PM UTC+1, John Myles White wrote:
>
> Sounds like we need to rerun these benchmarks after the new GC branch gets 
> updated.
>
>  -- John
>
> On Jun 17, 2014, at 9:31 AM, Stefan Karpinski <[email protected] 
> <javascript:>> wrote:
>
> That definitely smells like a GC issue. Python doesn't have this 
> particular problem since it uses reference counting.
>
>
> On Tue, Jun 17, 2014 at 12:21 PM, Cristóvão Duarte Sousa <[email protected] 
> <javascript:>> wrote:
>
>> I've just done measurements of algorithm inner loop times in my machine 
>> by changing the code has shown in this commit 
>> <https://github.com/cdsousa/Comparison-Programming-Languages-Economics/commit/4f6198ad24adc146c268a1c2eeac14d5ae0f300c>
>> .
>>
>> I've found out something... see for yourself:
>>
>> using Winston
>> numba_times = readdlm("numba_times.dat")[10:end];
>> plot(numba_times)
>>
>>
>> <https://lh6.googleusercontent.com/-m1c6SAbijVM/U6BpmBmFbqI/AAAAAAAADdc/wtxnKuGFDy0/s1600/numba_times.png>
>> julia_times = readdlm("julia_times.dat")[10:end];
>> plot(julia_times)
>>
>>
>> <https://lh4.googleusercontent.com/-7iprMnjyZQY/U6Bp8gHVNJI/AAAAAAAADdk/yUgu8RyZ-Kw/s1600/julia_times.png>
>> println((median(numba_times), mean(numba_times), var(numba_times)))
>> (0.0028225183486938477,0.0028575707378805993,2.4830103817464292e-8)
>>
>> println((median(julia_times), mean(julia_times), var(julia_times)))
>> (0.0028240440000000004,0.0034863882123824454,1.7058255003790299e-6)
>>
>> So, while inner loop times have more or less the same median on both 
>> Julia and Numba tests, the mean and variance are higher in Julia.
>>
>> Can that be due to the garbage collector being kicking in?
>>
>>
>> On Monday, June 16, 2014 4:52:07 PM UTC+1, Florian Oswald wrote:
>>>
>>> Dear all,
>>>
>>> I thought you might find this paper interesting: http://economics.
>>> sas.upenn.edu/~jesusfv/comparison_languages.pdf
>>>
>>> It takes a standard model from macro economics and computes it's 
>>> solution with an identical algorithm in several languages. Julia is roughly 
>>> 2.6 times slower than the best C++ executable. I was bit puzzled by the 
>>> result, since in the benchmarks on http://julialang.org/, the slowest 
>>> test is 1.66 times C. I realize that those benchmarks can't cover all 
>>> possible situations. That said, I couldn't really find anything unusual in 
>>> the Julia code, did some profiling and removed type inference, but still 
>>> that's as fast as I got it. That's not to say that I'm disappointed, I 
>>> still think this is great. Did I miss something obvious here or is there 
>>> something specific to this algorithm? 
>>>
>>> The codes are on github at 
>>>
>>> https://github.com/jesusfv/Comparison-Programming-Languages-Economics
>>>
>>>
>>>
>
>

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