From: Junio C Hamano <gitster@pobox.com>
To: Alexander Monakov <amonakov@ispras.ru>
Cc: git@vger.kernel.org, Phillip Wood <phillip.wood@dunelm.org.uk>
Subject: Re: [PATCH 0/2] optimize string hashing in xdiff
Date: Mon, 28 Jul 2025 12:32:11 -0700 [thread overview]
Message-ID: <xmqqa54oun5w.fsf@gitster.g> (raw)
In-Reply-To: <20250728190520.10962-1-amonakov@ispras.ru> (Alexander Monakov's message of "Mon, 28 Jul 2025 22:05:18 +0300")
Alexander Monakov <amonakov@ispras.ru> writes:
> I've noticed the work by Phillip Wood regarding hash optimization for xdiff.
> I want to point out that it is possible to speed up the existing hash by 1.5x
> matching the peformance of xxhash (but without introducing a dependendency).
Using xxhash() was merely a sample code path for technology
demonstration, so the Rust adoption topic may want to pick a
different code path to do its thing.
> The additive variant of the djb2 hash is used in ELF symbol lookup, and
> Noah Goldstein contributed a well-optimized implementation to Glibc.
What is the licensing terms for that code you are proposing us to
borrow? If it is anything recent in GNU, I'd expect that it would
be GPLv3, which would be incompatible with our code base?
> I'm taking the refactoring patch from Phillip and building on top of it.
It is an obviously good approach to do this.
next prev parent reply other threads:[~2025-07-28 19:32 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-07-28 19:05 [PATCH 0/2] optimize string hashing in xdiff Alexander Monakov
2025-07-28 19:05 ` [PATCH 1/2] xdiff: refactor xdl_hash_record() Alexander Monakov
2025-07-28 19:05 ` [PATCH 2/2] xdiff: optimize xdl_hash_record_verbatim Alexander Monakov
2025-07-28 20:50 ` Junio C Hamano
2025-07-28 20:57 ` Alexander Monakov
2025-08-04 13:49 ` Phillip Wood
2025-08-04 14:39 ` Alexander Monakov
2025-08-11 13:13 ` Phillip Wood
2025-08-11 14:14 ` Alexander Monakov
2025-08-12 17:56 ` Alexander Monakov
2025-08-20 21:34 ` Junio C Hamano
2025-09-08 19:06 ` Alexander Monakov
2025-09-08 21:04 ` Junio C Hamano
2025-08-13 13:10 ` Phillip Wood
2025-07-28 19:32 ` Junio C Hamano [this message]
2025-07-28 19:56 ` [PATCH 0/2] optimize string hashing in xdiff Eli Schwartz
2025-07-28 20:54 ` Junio C Hamano
2025-07-28 20:25 ` Alexander Monakov
2025-08-14 15:01 ` Junio C Hamano
2025-08-28 23:40 ` Junio C Hamano
2025-08-29 1:13 ` Jacob Keller
2025-08-29 3:09 ` Elijah Newren
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