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Re: 5.8.2-RC1 and mp2

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From:
Nicholas Clark
Date:
October 30, 2003 12:48
Subject:
Re: 5.8.2-RC1 and mp2
Message ID:
20031030204830.GC6287@plum.flirble.org
On Thu, Oct 30, 2003 at 02:08:06PM -0600, Scott A Crosby wrote:
> On Thu, 30 Oct 2003 19:25:17 +0000, Nicholas Clark <nick@ccl4.org> writes:

> Enlightenment. Thanks, looks good.

Thanks for over checking this for us.

> No need. For N= 10^9, the constant would be 20. Just use that. Assume
> you are under attack (or observing pathological inputs) if any hash
> chain has >20 elements.
> 
> Sorry, no patch.

It's easier not to send a patch, given that it's a s/4/20/ in 1 line.
[Although I'm actually going to commit MJD's suggestion of 14 for now]

> It leaves behind a VERY small opening for a very minor attack --- at
> worst a slight degradation. Thats a small enough impact that no
> attacker would bother with it.

Given Abigail's results that hashing a long list of words is faster on 5.8.2
RC1, I think (er, hope?) that we may find that we can tune the call to
split (and other parts of the hash routines) and see some performance
gains. But not for 5.8.2.

[patches and associated glory welcome :-) But If no-one else does it I'll
 try to claim the glory.]

Nicholas Clark

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