• a11e99z (3/3) Oct 01 2019 does anybody some kind of benchmark to test conservative and
• a11e99z (9/14) Oct 01 2019 are this 2 -DRT params combined or overwriting each other?
• Mike Parker (8/11) Oct 01 2019 Simple solution: don't allocate every frame. The GC only runs
• Rainer Schuetze (15/30) Oct 01 2019 Without false pointers the precise GC is usually a bit slower (by a few
• a11e99z (3/3) Oct 02 2019 On Wednesday, 2 October 2019 at 06:41:28 UTC, Rainer Schuetze

a11e99z <black80 bk.ru> writes:

does anybody some kind of benchmark to test conservative and 
precise GC?
precise GC is better or not? is STW improving?

a11e99z <black80 bk.ru> writes:

On Tuesday, 1 October 2019 at 16:12:18 UTC, a11e99z wrote:
 does anybody some kind of benchmark to test conservative and 
 precise GC?
 precise GC is better or not? is STW improving?

and another question about GC and app parameters:
 program.exe “–DRT-gcopt=gc:precise parallel:4” 
 “–DRT-scanDataSeg=precise” <input.data >output.data

are this 2 -DRT params combined or overwriting each other?
link to doc for DRT+GC 
https://dlang.org/spec/garbage.html#gc_config

I know about rt_options[] but asking about program args

why I want to know such info?
CodinGame sometimes use time-limit for bot move for example 
100ms, and bot will be disqualified in case no answer

Mike Parker <aldacron gmail.com> writes:

On Tuesday, 1 October 2019 at 16:24:49 UTC, a11e99z wrote:

 why I want to know such info?
 CodinGame sometimes use time-limit for bot move for example 
 100ms, and bot will be disqualified in case no answer

Simple solution: don't allocate every frame. The GC only runs 
when it needs to and it only needs to if an allocation request 
takes it over a certain threshold. If you need to allocate at 
all, do it up front. Or better, do it statically. Then the GC 
won't run at all.

What sort of CodinGame bot would you need to allocate from the GC 
for anyway?

Rainer Schuetze <r.sagitario gmx.de> writes:

On 01/10/2019 18:24, a11e99z wrote:
 On Tuesday, 1 October 2019 at 16:12:18 UTC, a11e99z wrote:
 does anybody some kind of benchmark to test conservative and precise GC?
 precise GC is better or not? is STW improving?


Without false pointers the precise GC is usually a bit slower (by a few
%) due to additional work being done during allocations. But it can be a
lot faster if there are false pointers that pin large amounts of memory
still needed to be scanned during collections. False pointers are more
likely for 32-bit processes, but can also happen with 64-bit processes
(also depending on addresses used by OS allocations: OSX worse than
Windows worse than Linux).

 
 and another question about GC and app parameters:
 program.exe “–DRT-gcopt=gc:precise parallel:4”
 “–DRT-scanDataSeg=precise” <input.data >output.data

 are this 2 -DRT params combined or overwriting each other?
 link to doc for DRT+GC https://dlang.org/spec/garbage.html#gc_config

These options are independent and can be used in arbitrary order. The
last option wins if you actually overwrite an option, e.g.
'“–DRT-gcopt=gc:precise parallel:4” “–DRT-gcopt=parallel:7”' will
still
use the precise GC, but 7 mark threads.

Please note that “–DRT-scanDataSeg=precise” is only supported on Windows.

 
 I know about rt_options[] but asking about program args
 
 why I want to know such info?
 CodinGame sometimes use time-limit for bot move for example 100ms, and
 bot will be disqualified in case no answer

There is no actual upper limit for the collection time, it mostly
depends on how much life memory has to be scanned.

a11e99z <black80 bk.ru> writes:

On Wednesday, 2 October 2019 at 06:41:28 UTC, Rainer Schuetze 
wrote:

thanks for the detailed answer