At this point, the only data structures we allocate directly in fcontext are the SQLFunctionCache struct itself, the ParamListInfo struct, and the execution_state array, all of which are small and perfectly capable of being re-used across executions of the same FmgrInfo. Hence, let's give them the same lifespan as the FmgrInfo. This step gets rid of the separate SQLFunctionLink struct and makes fn_extra point to SQLFunctionCache again. We also get rid of the separate fcontext memory context and allocate these items directly in fn_mcxt. For notational simplicity, SQLFunctionCache still has an fcontext field, but it's just a copy of fn_mcxt. The motivation for this is to allow these structures to live as long as the FmgrInfo and be re-used across calls, restoring the original design without its propensity for memory leaks. This gets rid of some per-call overhead that we added in0dca5d68d. We also make an effort to re-use the JunkFilter and result slot. Those might need to change if the function definition changes, so we compromise by rebuilding them if the cached plan changes. This also moves the tuplestore into fn_mcxt so that it can be re-used across calls, again undoing a change made in0dca5d68d.
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/.