Re: pg_trgm Memory Allocation logic

Beena Emerson wrote:
> In the pg_trgm module, within function generate_trgm, the memory for trigrams
> is allocated as follows:
> 
> trg = (TRGM *) palloc(TRGMHDRSIZE + sizeof(trgm) * (slen / 2 + 1) *3);
> 
> I have been trying to understand why this is so because it seems to be
> allocating more space than that is required.

Maybe it's considering a worst-case for multibyte characteres?  I don't
really know if trgm supports multibyte, but I assume it does.  If it
does, then probably the trigrams consist of chars, not bytes.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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