Previously, SIGINT was treated the same as SIGTERM in walwriter and
walsummarizer. That decision goes back to when the walwriter process
was introduced (commit ad4295728e), and was later copied to
walsummarizer. It was a pretty arbitrary decision back then, and we
haven't adopted that convention in all the other processes that have
been introduced later.
Summary of how other processes respond to SIGINT:
- Autovacuum launcher: Cancel the current iteration of launching
- bgworker: Ignore (unless connected to a database)
- checkpointer: Request shutdown checkpoint
- bgwriter: Ignore
- pgarch: Ignore
- startup process: Ignore
- walreceiver: Ignore
- IO worker: die()
IO workers are a notable exception in that they exit on SIGINT, and
there's a documented reason for that: IO workers ignore SIGTERM, so
SIGINT provides a way to manually kill them. (They do respond to
SIGUSR2, though, like all the other processes that we don't want to
exit immediately on SIGTERM on operating system shutdown.)
To make this a little more consistent, ignore SIGINT in walwriter and
walsummarizer. They have no "query" to cancel, and they react to
SIGTERM just fine.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/818bafaf-1e77-4c78-8037-d7120878d87c@iki.fi
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.
Copyright and license information can be found in the file COPYRIGHT.
Heikki Linnakangas
a92b809f9d