>Andrea, may I reorder your questions?
Sure you're welcome ;).
>>And what is `hash'? The input of the hashfn of buffers are blocks and dev.
>
>Chuck tuned various hash functions, and only the buffer cache uses
>blocks and dev. hash is a generic substitution. In my description I
>used 'k' up to this point.
Ah ok. Fine. (I thought you was talking specifically about the buffer
hash)
>Since my hash table size is 16384 and thus (32 - HASH_BITS) = 18 the
>'normalized' hashfn is:
>
> i = ((k * 2654435761UL) >> 11) & bh_hash_mask
> = ((k * 2654435761UL) << ((32 - HASH_BITS) - 11)) >> (32 - HASH_BITS)
I don't think the above is correct. If you don't shift left for (32 -
HASH_BITS) at least at once, then you may have still some bit set to 1 in
the high part of `i'.
Andrea Arcangeli
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