Re: Inaccuracy in VACUUM's tuple count estimates - Mailing list pgsql-hackers

From tim_wilson
Subject Re: Inaccuracy in VACUUM's tuple count estimates
Date
Msg-id 1403743371788-5809273.post@n5.nabble.com
Whole thread Raw
In response to Re: Inaccuracy in VACUUM's tuple count estimates  (Andres Freund <andres@2ndquadrant.com>)
Responses Re: Inaccuracy in VACUUM's tuple count estimates  (tim_wilson <tim.wilson@telogis.com>)
List pgsql-hackers
Given that this seems to have slipped off the hackers radar (or in too hard
basket) I have constructed a horrible solution.

I will stop using autovacuum for this relation , I will use our own system
to monitor the relation, and I will reset pgclass.reltuples on this relation
after vacuum is done to the correct value.

I note that vacuum.c has comments in vac_update_relstat that changes to
pg_class are done without a transaction. Are there dangers of my doing an 
update pg_class set reltuples=60000 where relkind='r' and
relname='my_hot_table' ? 







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