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From: Junio C Hamano <gitster@pobox.com>
Subject: Re: Migrating away from SHA-1?
Date: Thu, 14 Apr 2016 19:18:53 -0700
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Cc: Theodore Ts'o <tytso@mit.edu>, "H. Peter Anvin" <hpa@zytor.com>,
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To: Jeff King <peff@peff.net>
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In-Reply-To: <20160415021327.GC22112@sigill.intra.peff.net> (Jeff King's
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Jeff King <peff@peff.net> writes:

> [2] Somewhere in the list archive is my patch to find partial
>     collisions like "git commit --sha1=31337", and I did in fact use
>     that micro-optimization. That, along with multi-threading, made it
>     feasible to do 6-8 character prefixes, as I recall.

In our testsuite, we have a test that uses many objects, all of
which have object names that begin with 10 '0' characters.