git.postgresql.org Git - postgresql.git/commit

git projects / postgresql.git / commit

summary | shortlog | log | commit | commitdiff | tree
(parent: fbfe691) | patch

Add single-item cache when looking at topmost XID of a subtrans XID

Add single-item cache when looking at topmost XID of a subtrans XID

This change affects SubTransGetTopmostTransaction(), used to find the
topmost transaction ID of a given transaction ID. The cache is able to
store one value, so as we can save the backend from unnecessary lookups
at pg_subtrans/ on repetitive calls of this routine. There is a similar
practice in transam.c, for example.

Author: Simon Riggs
Reviewed-by: Andrey Borodin, Julien Rouhaud
Discussion: https://postgr.es/m/CANbhV-G8Co=yq4v4BkW7MJDqVt68K_8A48nAZ_+8UQS7LrwLEQ@mail.gmail.com

RSS Atom