Tom Lane 8a40697660 Fix a recently-introduced race condition in LISTEN/NOTIFY handling. ... Commit 566372b3d fixed some race conditions involving concurrent SimpleLruTruncate calls, but it introduced new ones in async.c. A newly-listening backend could attempt to read Notify SLRU pages that were in process of being truncated, possibly causing an error. Also, the QUEUE_TAIL pointer could become set to a value that's not equal to the queue position of any backend. While that's fairly harmless in v13 and up (thanks to commit 51004c717), in older branches it resulted in near-permanent disabling of the queue truncation logic, so that continued use of NOTIFY led to queue-fill warnings and eventual inability to send any more notifies. (A server restart is enough to make that go away, but it's still pretty unpleasant.) The core of the problem is confusion about whether QUEUE_TAIL represents the "logical" tail of the queue (i.e., the oldest still-interesting data) or the "physical" tail (the oldest data we've not yet truncated away). To fix, split that into two variables. QUEUE_TAIL regains its definition as the logical tail, and we introduce a new variable to track the oldest un-truncated page. Per report from Mikael Gustavsson. Like the previous patch, back-patch to all supported branches. Discussion: https://postgr.es/m/1b8561412e8a4f038d7a491c8b922788@smhi.se		2020-11-28 14:03:40 -05:00
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backend	Fix a recently-introduced race condition in LISTEN/NOTIFY handling.	2020-11-28 14:03:40 -05:00
bin	Ignore attempts to \gset into specially treated variables.	2020-11-09 07:32:14 -08:00
common	Replace use of sys_siglist[] with strsignal().	2020-07-15 22:05:13 -04:00
fe_utils	Fix translation of special characters in psql's LaTeX output modes.	2018-11-26 17:32:51 -05:00
include	Properly check index mark/restore in ExecSupportsMarkRestore.	2020-11-24 21:19:50 +00:00
interfaces	Stamp 9.6.20.	2020-11-09 17:32:22 -05:00
makefiles	Select CFLAGS_SL at configure time, not in platform-specific Makefiles.	2019-10-21 12:32:36 -04:00
pl	Translation updates	2020-11-09 12:47:52 +01:00
port	Stamp 9.6.20.	2020-11-09 17:32:22 -05:00
template	On macOS, use -isysroot in link steps as well as compile steps.	2020-11-20 00:58:26 -05:00
test	Further fixes for CREATE TABLE LIKE: cope with self-referential FKs.	2020-11-19 15:03:17 -05:00
timezone	Update time zone data files to tzdata release 2020d.	2020-10-22 21:24:23 -04:00
tools	Sync our copy of the timezone library with IANA release tzcode2020c.	2020-10-16 21:40:16 -04:00
tutorial	Update copyright for 2016	2016-01-02 13:33:40 -05:00
.gitignore	Convert cvsignore to gitignore, and add .gitignore for build targets.	2010-09-22 12:57:04 +02:00
bcc32.mak	Autoconfiscate selection of 64-bit int type for 64-bit large object API.	2012-10-07 21:52:43 -04:00
DEVELOPERS	Replace a couple of references to files that no longer exist in the source	2009-05-04 08:08:47 +00:00
Makefile	Install TAP test infrastructure so it's available for extension testing.	2016-09-23 15:50:00 -04:00
Makefile.global.in	Select CFLAGS_SL at configure time, not in platform-specific Makefiles.	2019-10-21 12:32:36 -04:00
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	nls-global.mk: search build dir for source files, too	2016-06-07 18:55:18 -04:00
win32.mak	Autoconfiscate selection of 64-bit int type for 64-bit large object API.	2012-10-07 21:52:43 -04:00