Hi, On 07/21/2017 03:40 PM, Alexander Korotkov wrote: > Hi, Alexey! > > On Fri, Jul 21, 2017 at 3:05 PM, Alexey Chernyshov > <a.chernys...@postgrespro.ru <mailto:a.chernys...@postgrespro.ru>> wrote: > > the following patch transfers functionality from gevel module > (http://www.sai.msu.su/~megera/wiki/Gevel > <http://www.sai.msu.su/~megera/wiki/Gevel>) which provides functions for > analyzing GIN and GiST indexes to pageinspect. Gevel was originally > designed by Oleg Bartunov, and Teodor Sigaev for developers of GiST and > GIN indexes. > > > It's very good that you've picked up this work! pageinspect is lacking > of this functionality. > > Functions added: > - gist_stat(text) - shows statistics on GiST Tree > - gist_tree(text) - shows GiST tree > - gist_tree(text, int4) - shows GiST tree up to MAXLEVEL > - gist_print(text) - prints objects stored in GiST tree > - spgist_stat(text) - shows statistics on SP-GiST > - spgist_print(text) - prints objects stored in index > - gin_value_count() - originally gin_stat(text) - prints estimated > counts > for index values > - gin_stats() - originally gin_statpage(text) - shows statistics > - gin_count_estimate(text, tsquery) - shows number of indexed rows > matched > query > > Tests also transferred, docs for new functions are added. I run pgindent > over the code, but the result is different from those I expected, so > I leave > pgindented one. > The patch is applicable to the commit > 866f4a7c210857aa342bf901558d170325094dde. > > > As we can see, gevel contains functions which analyze the whole index. > pageinspect is written in another manner: it gives you functionality to > analyze individual pages, tuples and so on. > Thus, we probably shouldn't try to move gevel functions to pageinspect > "as is". They should be rewritten in more granular manner as well as > other pageinspact functions are. Any other opinions? >
I agree with Alexander that pageinspect is written in a very different way - as the extension name suggests, it's used to inspect pages. The proposed patch uses a very different approach, reading the whole index, not individual pages. Why should it be part of pageinspect? For example we have pgstattuple extension, which seems like a better match. Or just create a new extension - if the code is valuable, surely we can live one more extension instead of smuggling it in inside pageinspect. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
