zlib performance

[yawniek via Digitalmars-d-learn]

On Friday, 7 August 2015 at 08:24:11 UTC, Daniel Kozák wrote:

> can you try it with ldc?
>
> ldc[2] -O -release -boundscheck=off -singleobj  app.d


ldc 0.15.2 beta2
2.86s user 0.55s system 77% cpu 4.392 total

v2.068-devel-8f81ffc
2.86s user 0.67s system 78% cpu 4.476 total

v2.067
2.88s user 0.67s system 78% cpu 4.529 total

(different file, half the size of the one above:)
archlinux, virtualbox vm, DMD64 D Compiler v2.067
real	0m2.079s
user	0m1.193s
sys	0m0.637s

zcat:
real	0m3.023s
user	0m0.320s
sys	0m2.440s


is there a way to get rid of the flush in the end so everything 
happens in one loop? its a bit inconvenient when i have another 
subloop that does work