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Date: Tue, 2 Jul 2024 17:49:26 +0200
Message-ID: <CAP1Jc138wu1wpu2FaEW_aOPbYXzgYK4WXqzbkxz3_-Ca7v1kdQ@mail.gmail.com>
Subject: Re: [PHP-DEV] [RFC] Lazy Objects
To: =?UTF-8?Q?Tim_D=C3=BCsterhus?= <tim@bastelstu.be>
Cc: Marco Pivetta <ocramius@gmail.com>, Nicolas Grekas <nicolas.grekas+php@gmail.com>, 
	PHP Internals List <internals@lists.php.net>
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From: arnaud.lb@gmail.com (Arnaud Le Blanc)

Hi Tim,

On Sun, Jun 30, 2024 at 3:54=E2=80=AFPM Tim D=C3=BCsterhus <tim@bastelstu.b=
e> wrote:
> On 6/27/24 16:27, Arnaud Le Blanc wrote:
> >>   * flags should be a `list<SomeEnumAroundProxies>` instead. A bitmask=
 for
> >> a new API feels unsafe and anachronistic, given the tiny performance h=
it.
> >>
> >
> > Unfortunately this leads to a 30% slowdown in newLazyGhost() when switc=
hing
> > to an array of enums, in a micro benchmark. I'm not sure how this would
> > impact a real application, but given this is a performance critical
>
> I'm curious, how did the implementation look like? Is there a proof of
> concept commit or patch available somewhere? As the author of the first
> internal enum (Random\IntervalBoundary) I had the pleasure of finding
> out that there was no trivial way to efficiently match the various enum
> cases. See the PR review here:
> https://github.com/php/php-src/pull/9679#discussion_r1045943444

I've benchmarked this implementation:
https://github.com/arnaud-lb/php-src/commit/f5f87d8a7abeba2f406407606949e5c=
6e512baab.
Using a backed enum to have a more direct way to map enum cases to
integers didn't make a significant difference.
Here is the benchmark:
https://gist.github.com/arnaud-lb/76f77b5d7409a9e4deea995c179c6e96.
Caching the options array between calls had a less dramatic slowdown
(around 10%): https://gist.github.com/arnaud-lb/87e7f58cc11463dd3aa098218eb=
95a90.

Best Regards,
Arnaud