02c4bc8830
I noticed the surprising behavior that pg_sleep(0.001) will sleep for 2ms not the expected 1ms. Apparently the float8 calculation of time-to-sleep is managing to produce something a hair over 1, which ceil() rounds up to 2, and then WaitLatch() faithfully waits 2ms. It could be that this works as-expected for some ranges of current timestamp but not others, which would account for not having seen it before. In any case, let's try to avoid it by removing the float arithmetic in the delay calculation. We're stuck with the declared input type being float8, but we can convert that to integer microseconds right away, and then work strictly with integral values. There might still be roundoff surprises for certain input values, but at least the behavior won't be time-varying. Author: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Robert Haas <robertmhaas@gmail.com> Reviewed-by: Nathan Bossart <nathandbossart@gmail.com> Discussion: https://postgr.es/m/3879137.1758825752@sss.pgh.pa.us
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.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.