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From: Jeff King <peff@peff.net>
To: Stefan Beller <stefanbeller@gmail.com>
Cc: Patrick Reynolds <patrick.reynolds@github.com>,
	Git <git@vger.kernel.org>
Subject: Re: [PATCH v2] use a hashmap to make remotes faster
Date: Fri, 5 Sep 2014 11:16:26 -0400	[thread overview]
Message-ID: <20140905151626.GA1846@peff.net> (raw)
In-Reply-To: <5409887A.1000602@gmail.com>

On Fri, Sep 05, 2014 at 11:55:06AM +0200, Stefan Beller wrote:

> >  struct remote {
> > +	struct hashmap_entry ent;  /* must be first */
> > +
> 
> I stumbled about this comment  "/* must be first */"
> when reading the changelog.
> 
> Why does it need to be first?
> Is it a common reason I'm just not aware of,
> or would it make sense to put the reason into the comment as well?

Yes, it's a requirement of the hashmap code. It stores arbitrary
structs, but uses the front of the type for its bookkeeping data (the
hash and a linked list pointer to the next item in the bucket). This is
documented in Documentation/technical/api-hashmap.txt.

-Peff

      reply	other threads:[~2014-09-05 15:16 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-29 14:43 [PATCH v2] use a hashmap to make remotes faster Patrick Reynolds
2014-07-29 17:46 ` Jeff King
2014-07-30 18:26 ` Junio C Hamano
2014-09-05  9:55 ` Stefan Beller
2014-09-05 15:16   ` Jeff King [this message]

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