Message-ID: <450464da0611290257i50116402m4b2d97fc303ec374@mail.gmail.com>
Date: Wed, 29 Nov 2006 21:57:05 +1100
From: "Robbie Gates" <robbie@m8s.org>
To: cygwin@cygwin.com
Subject: Re: FYI - bash crash due to asprintf bug
In-Reply-To: <456CF7D9.3090801@byu.net>
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> reduces asprintf's use of realloc from quadratic
> to log-linear performance (ie. calling realloc every time you add a byte
> is bad, compared to doubling the buffer size every time you call realloc).

Just out of interest, note that a size increase of 50% (i.e. new size
= (3*oldsize)/2) has better properties for certain memory managers, as
opposed to doubling. It has the same asymptotic complexity improvement
as doubling. Roughly speaking, any factor less than the golden ratio
(1+sqrt(5))/2 is good, but 1.5 is (a) cheaply obtanied on most cpu
architectures, and (b) leaves a little space in case the memory
manager adds some overhead. See http://tinyurl.com/yd5669 for details.

 - robbie

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