Re: Re: Fast string hash in portable perl?

CRC32 is not a good choice for hashing strings for lookup purposes. There are too many collosion hotspots. And MD5 isn't a 32-bit value.

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Comment on Re: Re: Fast string hash in portable perl?

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Re: Re: Re: Fast string hash in portable perl? by flyingmoose (Priest) on Dec 19, 2003 at 20:56 UTC
Not 32 bit? Then just run the B::hash on the MD5! Just kidding folks, just kidding! You are exactly right on CRC32. I can't think of any case where CRC32 is really a good choice.	[reply]
Re: Re: Re: Re: Fast string hash in portable perl? by waswas-fng (Curate) on Dec 19, 2003 at 22:15 UTC
CRC32 may be a great choice if you use it as the quick test for changes and then use a less collision prone (more time/cpu intensive) hash generator for a secondary test. Kind of what rsync does to speed up the block level checking. -Waswas	[reply]