On Friday, May 1, 2015 at 11:48:21 AM UTC-4, Tim Holy wrote:
>
> On Friday, May 01, 2015 08:03:31 AM Scott Jones wrote: 
> > Still, same issue as I described above... probably better to increase by 
> 2x 
> > up to a point, and then by chunk sizes, where the chunk sizes might 
> slowly 
> > get larger... 
>
> I see your point, but it will also break the O(nlogn) scaling. We couldn't 
> hard-code the cutoff, because some people run julia on machines with 4GB 
> of RAM 
> and others with 1TB of RAM. So, we could query the amount of RAM available 
> and 
> switch based on that result, but since all this would only make a 
> difference 
> for operations that consume between 0.5x and 1x the user's RAM (which to 
> me 
> seems like a very narrow window, on the log scale), is it really worth the 
> trouble? 
>
> --Tim 
>

For what I was doing, yes, it was definitely worth the trouble, because 
you'd have systems with 10s of thousands of processes (the limit was 64K on 
a single node), and you had to be very careful about not using up too much 
memory, and ending up thrashing...
Very different than when you maybe have a process for each core, and you 
have lots of memory for each one...
Different usage... different performance issues... 

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