Re: consistant failures on a new kind of spam

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Jem wrote:
> Brian I thought that the built-in hash database (Hashed-array-cached) had a 
> fixed size, presumably because a hash collision just overwrites a hash 
> entry. So I thought whether you clean it or not, a collision will lead to a 
> term being overwritten. Or are you saying it grows to a list at collision?

Oh, and collision can mean one to two things.  In my email I was 
referring to two different hash codes mod'd to the same index into the 
array.  I think you were referring to the second (and nastier) kind of 
collision which is when two different terms hash to the same hash code.

In the latter case you are right that a term can wind up being 
overwritten due to a hash collision.  I think my testing of the hash 
algorithm showed a very small number of this type of collision in my own 
email.

The former case (two codes mod to same index) is harmless except that it 
impacts performance as I described in my other email.

And you are correct that neither case will cause the file to grow in 
size.  The hash files are fixed size and can become too full to hold new 
terms.

Thanks,
++Brian

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