9dcc764144
Increase the size of the "direct" histogram to 10K elements, so that we can precisely track loop times up to 10 microseconds. (Going further than that seems pretty uninteresting, even for very old and slow machines.) Relabel "Per loop time" as "Average loop time" for clarity. Pre-zero the histogram arrays to make sure that they are loaded into processor cache and any copy-on-write overhead has happened before we enter the timing loop. Also use unlikely() to keep the compiler from thinking that the clock-went-backwards case is part of the hot loop. Neither of these hacks made a lot of difference on my own machine, but they seem like they might help on some platforms. Discussion: https://postgr.es/m/be0339cc-1ae1-4892-9445-8e6d8995a44d@eisentraut.org
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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