Tomas Vondra 6ca015f9f0 Track unowned relations in doubly-linked list ... Relations dropped in a single transaction are tracked in a list of unowned relations. With large number of dropped relations this resulted in poor performance at the end of a transaction, when the relations are removed from the singly linked list one by one. Commit b4166911 attempted to address this issue (particularly when it happens during recovery) by removing the relations in a reverse order, resulting in O(1) lookups in the list of unowned relations. This did not work reliably, though, and it was possible to trigger the O(N^2) behavior in various ways. Instead of trying to remove the relations in a specific order with respect to the linked list, which seems rather fragile, switch to a regular doubly linked. That allows us to remove relations cheaply no matter where in the list they are. As b4166911 was a bugfix, backpatched to all supported versions, do the same thing here. Reviewed-by: Alvaro Herrera Discussion: https://www.postgresql.org/message-id/flat/80c27103-99e4-1d0c-642c-d9f3b94aaa0a%402ndquadrant.com Backpatch-through: 9.4		2019-03-27 02:39:39 +01:00
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backend	Track unowned relations in doubly-linked list	2019-03-27 02:39:39 +01:00
bin	psql: Schema-qualify typecast in one \d query	2019-03-26 13:06:41 -03:00
common	Refactor more code logic to update the control file	2019-03-18 12:59:35 +09:00
fe_utils	pgbench: Remove \cset	2019-03-25 12:16:07 -03:00
include	Track unowned relations in doubly-linked list	2019-03-27 02:39:39 +01:00
interfaces	Restructure libpq's handling of send failures.	2019-03-19 16:20:28 -04:00
makefiles	Move port-specific parts of with_temp_install to port makefile.	2019-02-04 18:54:56 +00:00
pl	Transaction chaining	2019-03-24 11:33:02 +01:00
port	Fix error handling of readdir() port implementation on first file lookup	2019-03-04 09:49:06 +09:00
template	Yet further rethinking of build changes for macOS Mojave.	2018-11-02 18:54:00 -04:00
test	Fix partitioned index creation bug with dropped columns	2019-03-26 20:19:28 -03:00
timezone	More unconstify use	2019-02-13 11:50:16 +01:00
tools	Compute XID horizon for page level index vacuum on primary.	2019-03-26 16:52:54 -07:00
tutorial	SQL comment: remove extra word in heading comment	2019-01-25 18:57:21 -05:00
.gitignore	…
DEVELOPERS	…
Makefile	…
Makefile.global.in	Revert attempts to use POPCNT etc instructions	2019-02-15 16:32:30 -03:00
Makefile.shlib	Ensure static libraries have correct mod time even if ranlib messes it up.	2018-11-29 15:53:44 -05:00
nls-global.mk	Replace @postgresql.org with @lists.postgresql.org for mailinglists	2019-01-19 19:06:35 +01:00