From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Shawn O. Pearce" <spearce@spearce.org>
Subject: Re: [PATCH] pack-object: trim memory usage a tiny bit
Date: Fri, 6 Aug 2010 17:18:29 -0700
Message-ID: <20100807001829.GQ25268@spearce.org>
References: <1281114057-5982-1-git-send-email-pclouds@gmail.com> <AANLkTikphara-0NXaBZ-MAygytGYDuN6ANcMWE+Ni3mW@mail.gmail.com> <AANLkTikL8MtqFr1T=3TKA7GLKSEbyvf+6SLTT2BYehto@mail.gmail.com> <AANLkTingdhx5osnbiLVMyWaauCf1TRiMzcSC76gQRp9B@mail.gmail.com> <AANLkTimEFjRuuO+GnAV7PGe0oPi-Qh37iLS6o3Q8Undw@mail.gmail.com>
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Cc: Sverre Rabbelier <srabbelier@gmail.com>, git <git@vger.kernel.org>
To: Nguyen Thai Ngoc Duy <pclouds@gmail.com>
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Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:
> 
> Ah, by packing it tighter using bitfields. There are two fields that
> act as boolean, but they use at least one byte each. And enum
> object_type, I recall, uses 4 bytes (int), while it only needs 5 bits
> (4 bits is enough if OBJ_BAD is not counted). No downsides I know of.

Actually, object type is 3 bits in the pack file.  So unless its
using some additional magical values, 4 bits is sufficient to get
you 3 bits and the -1 bad value.

-- 
Shawn.