Consistently test for in-use shared memory. postmaster startup scrutinizes any shared memory segment recorded in postmaster.pid, exiting if that segment matches the current data directory and has an attached process. When the postmaster.pid file was missing, a starting postmaster used weaker checks. Change to use the same checks in both scenarios. This increases the chance of a startup failure, in lieu of data corruption, if the DBA does "kill -9 `head -n1 postmaster.pid` && rm postmaster.pid && pg_ctl -w start". A postmaster will no longer recycle segments pertaining to other data directories. That's good for production, but it's bad for integration tests that crash a postmaster and immediately delete its data directory. Such a test now leaks a segment indefinitely. No "make check-world" test does that. win32_shmem.c already avoided all these problems. In 9.6 and later, enhance PostgresNode to facilitate testing. Back-patch to 9.4 (all supported versions).
Reviewed by Daniel Gustafsson and Kyotaro HORIGUCHI. Discussion: https://postgr.es/m/20130911033341.gd225...@tornado.leadboat.com Branch ------ REL_10_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/7c414cdc39a3f183ff398be4cfcef0646f419281 Modified Files -------------- src/Makefile.global.in | 4 +- src/backend/port/sysv_shmem.c | 255 ++++++++++++++++++++---------------- src/backend/port/win32_shmem.c | 7 +- src/backend/postmaster/postmaster.c | 12 +- src/backend/storage/ipc/ipci.c | 14 +- src/backend/utils/init/postinit.c | 6 +- src/include/storage/ipc.h | 2 +- src/include/storage/pg_shmem.h | 6 +- src/test/perl/PostgresNode.pm | 182 ++++++++++++++++++++----- src/test/recovery/t/017_shm.pl | 154 ++++++++++++++++++++++ src/tools/msvc/vcregress.pl | 1 + 11 files changed, 467 insertions(+), 176 deletions(-)
