8b2bcf3f28
Presently, the most straightforward way for a shared library to use shared memory is to request it at server startup via a shmem_request_hook, which requires specifying the library in shared_preload_libraries. Alternatively, the library can create a dynamic shared memory (DSM) segment, but absent a shared location to store the segment's handle, other backends cannot use it. This commit introduces a registry for DSM segments so that these other backends can look up existing segments with a library-specified string. This allows libraries to easily use shared memory without needing to request it at server startup. The registry is accessed via the new GetNamedDSMSegment() function. This function handles allocating the segment and initializing it via a provided callback. If another backend already created and initialized the segment, it simply attaches the segment. GetNamedDSMSegment() locks the registry appropriately to ensure that only one backend initializes the segment and that all other backends just attach it. The registry itself is comprised of a dshash table that stores the DSM segment handles keyed by a library-specified string. Reviewed-by: Michael Paquier, Andrei Lepikhov, Nikita Malakhov, Robert Haas, Bharath Rupireddy, Zhang Mingli, Amul Sul Discussion: https://postgr.es/m/20231205034647.GA2705267%40nathanxps13 |
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| authentication | ||
| examples | ||
| icu | ||
| isolation | ||
| kerberos | ||
| ldap | ||
| locale | ||
| mb | ||
| modules | ||
| perl | ||
| recovery | ||
| regress | ||
| ssl | ||
| subscription | ||
| Makefile | ||
| README | ||
| meson.build | ||
README
PostgreSQL tests ================ This directory contains a variety of test infrastructure as well as some of the tests in PostgreSQL. Not all tests are here -- in particular, there are more in individual contrib/ modules and in src/bin. Not all these tests get run by "make check". Check src/test/Makefile to see which tests get run automatically. authentication/ Tests for authentication (but see also below) examples/ Demonstration programs for libpq that double as regression tests via "make check" isolation/ Tests for concurrent behavior at the SQL level kerberos/ Tests for Kerberos/GSSAPI authentication and encryption ldap/ Tests for LDAP-based authentication locale/ Sanity checks for locale data, encodings, etc mb/ Tests for multibyte encoding (UTF-8) support modules/ Extensions used only or mainly for test purposes, generally not suitable for installing in production databases perl/ Infrastructure for Perl-based TAP tests recovery/ Test suite for recovery and replication regress/ PostgreSQL's main regression test suite, pg_regress ssl/ Tests to exercise and verify SSL certificate handling subscription/ Tests for logical replication