Optimizing Java using D

[Joseph Rushton Wakeling via Digitalmars-d]

On 21/06/14 03:48, Peter Alexander via Digitalmars-d wrote:
> On Saturday, 21 June 2014 at 01:07:20 UTC, safety0ff wrote:
>> std.algorithm.sort with SwapStrategy.unstable is considerably slower than his,
>> whereas builtin sort is  abysmal.
>>
>> I find that generally using SwapStrategy.stable performs better.
>> This isn't universal though as there are cases where it is slower.
>
> wat
>
> Shouldn't unstable be faster, otherwise we might as well just alias unstable =
> stable!?

I can't find the issue in bugzilla, but IIRC there was a problem with unstable 
sort where it would produce worst-case-scenario behaviour in the event of being 
given input that had only a few unsorted elements.

I ran into it when implementing some of the algorithms in Dgraph: appending one 
new element to an array and using sort() would generate quadratic behaviour.

That case of "mostly sorted" input seems to also be present in the problem 
described here.