270caee04f
Converting xlog.c to the new shared memory allocation API left the
creation of the memory context used by wal_debug in the
XLOGShmemInit() callback, which now only runs in the postmaster or in
a standalone backend. Previously, XLOGShmemInit() ran in every child.
As a result, walDebugCtx was left uninitialized in child processes in
EXEC_BACKEND mode, and with wal_debug turned on, the backend crashed
on first WAL insertion.
Fix by moving the walDebugCtx initialization to a separate function
that is called in each backend that wishes to create WAL records. (It
cannot be created lazily on first WAL insertion, because it's done in
a critical section, and you cannot create a new memory context in a
critical section.)
Oversight in 9b5acad3f4.
Co-authored-by:: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/CALj2ACUNL4Xn3aBzvm4DTpdr_L0-AfL2agsghMRRy_ZTiKhxSA@mail.gmail.com
Backpatch-through: 19
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
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General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/19/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/19/installation.html.
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