Re: [PATCH v2 02/16] object-name: allow skipping ambiguity checks in `get_oid()` family

From: Jeff King <peff@peff.net>
Date: Feb 21, 2025, 08:00 UTC
Message-ID: <20250221080003.GD1988395@coredump.intra.peff.net>
In-Reply-To: <20250219-pks-update-ref-optimization-v2-2-e696e7220b22@pks.im>

On Wed, Feb 19, 2025 at 02:23:29PM +0100, Patrick Steinhardt wrote:

Show 8 quoted lines

> When reading an object ID via `get_oid_basic()` or any of its related
> functions we perform a check whether the object ID is ambiguous, which
> can be the case when a reference with the same name exists. While the
> check is generally helpful, there are cases where it only adds to the
> runtime overhead without providing much of a benefit.
> 
> Add a new flag that allows us to disable the check. The flag will be
> used in a subsequent commit.

If we are going to switch to this and get rid of the global warn_on_object_refname_ambiguity flag, I could see it being worth it.

But when I looked into doing that, it did not make much sense (there are too many code paths that share the same get_oid calls, and you'd have to plumb the flags through the stack).

So if we are going to leave the global flag anyway, and if your patch 3 is just changing all of update-ref to pass the per-call flag in every call, why don't we just skip this new mechanism and have update-ref unset the warn_on_object_refname_ambiguity flag?

That makes patch 3 a one-liner, and patches 1 and 2 can go away.

-Peff

PS Sorry, I haven't looked carefully at the rest of the series. I've
   been moving houses and am way back-logged on Git stuff, so don't
   count on me reviewing it anytime soon.