On Thursday, 13 January 2022 at 10:21:12 UTC, Stanislav Blinov
wrote:
On Wednesday, 12 January 2022 at 16:17:02 UTC, H. S. Teoh wrote:
[...]
Oh there is a psychological barrier for sure. On both sides of
the, uh, "argument". I've said this before but I can repeat it
again: time it. 4 milliseconds. That's how long a single
GC.collect() takes on my machine. That's a quarter of a frame.
And that's a dry run. Doesn't matter if you can GC.disable or
not, eventually you'll have to collect, so you're paying that
cost (more, actually, since that's not going to be a dry run).
If you can afford that - you can befriend the GC. If not - GC
goes out the window.
In other words, it's only acceptable if you have natural pauses
(loading screens, transitions, etc.) with limited resource
consumption between them OR if you can afford to e.g. halve
your FPS for a while. The alternative is to collect every
frame, which means sacrificing a quarter of runtime. No, thanks.
Thing is, "limited resource consumption" means you're
preallocating anyway, at which point one has to question why
use the GC in the first place. The majority of garbage created
per frame can be trivially allocated from an arena and
"deallocated" in one `mov` instruction (or a few of them). And
things that can't be allocated in an arena, i.e. things with
destructors - you *can't* reliably delegate to the GC anyway -
which means your persistent state is more likely to be manually
managed.
TLDR: it's pointless to lament on irrelevant trivia. Time it!
Any counter-arguments from either side are pointless without
that.
You collect it when it matters less, like loading a level, some
of them take so long that people even have written mini-games
that play during loading scenes, they won't notice a couple of ms
more.
Hardly any different from having an arena throw away the whole
set of frame data during loading.
Unless we start talking about DirectStorage and similar.
