Richard Whidden wrote:
Due to popular demand (1 person), I've compared sizes with 90 and 100 fillfactors, along with using the new GIN index.

First, GIN doesn't utilize fillfactor option yet.


Findings were not surprising, except for the GIN indexes, which doubled in size.
Second, In opposite to GiST, size of GIN index strongly depends on document collection. Each unique word in collection has list of pointer to document in which it occur. Size of pointer is a 6 byte. So word with 4 bytes length will occupy at least 4 + N_docs_with_word * 6.

Fortunately, for searching it's needed to read very small part of index, so GIN will be faster.



After several ALTER/RE INDEXes, here they are:

GiST
----
8.1 = 94990
8.2 FF90 = 106244 relpages (8k)
8.2 FF100 = 95049

GIN
---
FF100 = 197702


Richard Whidden

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Teodor Sigaev                                   E-mail: [EMAIL PROTECTED]
                                                   WWW: http://www.sigaev.ru/

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