https://issues.dlang.org/show_bug.cgi?id=19617

Basile-z <b2.temp@gmx.com> changed:

           What    |Removed                     |Added
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            Summary|[2.085a] Much slower code   |[REG 2.085a] Much slower
                   |compared to 2.084           |code compared to 2.084

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https://issues.dlang.org/show_bug.cgi?id=19617

Ketmar Dark <ketmar@ketmar.no-ip.org> changed:

           What    |Removed                     |Added
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                 CC|                            |ketmar@ketmar.no-ip.org

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https://issues.dlang.org/show_bug.cgi?id=19617

Basile-z <b2.temp@gmx.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|dmd                         |druntime
           Hardware|x86_64                      |All
            Summary|[REG 2.085a] Much slower    |[REG 2.085a] Much slower GC
                   |code compared to 2.084      |compared to 2.084
                 OS|Linux                       |All

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https://issues.dlang.org/show_bug.cgi?id=19617

--- Comment #1 from Basile-z <b2.temp@gmx.com> ---
So it's likely the GC that's slower not the cde generated. If you add a GC.dsiable; before start the stopwatch the timing are similar using 2.084 and ~master.

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https://issues.dlang.org/show_bug.cgi?id=19617

Rainer Schuetze <r.sagitario@gmx.de> changed:

           What    |Removed                     |Added
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                 CC|                            |r.sagitario@gmx.de

--- Comment #2 from Rainer Schuetze <r.sagitario@gmx.de> ---
There is little difference on my system between 2.083 and git HEAD, maybe 110 µs and 120 µs, respectively. These number are way too small for a benchmark as every unrelated detail can make a big difference. If I make the text longer so that the time is a about 1ms (still very small), the absolute difference is about the same if at all noticable in the noise.

The most likely related change in the GC is that intermediate allocation sizes are now supported, too (these were power of 2 only so far). This can lead to less memory being used for the same allocations (up to about 30%), but it also changes when collections are run. Appending to arrays might also reallocate a bit more often.

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https://issues.dlang.org/show_bug.cgi?id=19617

--- Comment #3 from Basile-z <b2.temp@gmx.com> ---
I didn't want to blame you or discredit your recent work on the GC Rainer. I'll try bigger benchmark and close the issue if it appears that I have over-reacted to a micro benchmark.

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https://issues.dlang.org/show_bug.cgi?id=19617

--- Comment #4 from Rainer Schuetze <r.sagitario@gmx.de> ---
No problem. I also noticed a couple of changes in the druntime benchmarks, some for the better, some for the worse. Those mostly boiled down to how many garbage collections are run which changes if memory is used differently.

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https://issues.dlang.org/show_bug.cgi?id=19617

Basile-z <b2.temp@gmx.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|---                         |INVALID

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