On 25 Feb 2016 11:05 pm, "Walter Bright via Digitalmars-d" <digitalmars-d@puremagic.com> wrote:
>
> On 2/25/2016 1:50 PM, Andrei Alexandrescu wrote:
>>
>> Good to know, thanks! -- Andrei
>
>
> DMD did slow down because it was now being compiled by DMD instead of g++. Also, dmd was doing multithreaded file I/O, but that was removed because speed didn't matter <grrrr>.
>

I thought that mulithreaded I/O did not change anything, or slowed compilation down in some cases?

Or I recall seeing a slight slowdown when I first tested it in gdc all those years ago.  So left it disabled - probably for the best too.