pgsql-server/ oc/src/sgml/runtime.sgml rc/back ...

CVSROOT:    /cvsroot
Module name:    pgsql-server
Changes by:    momjian@postgresql.org    03/03/19 23:51:44

Modified files:
    doc/src/sgml   : runtime.sgml
    src/backend/postmaster: postmaster.c
    src/backend/utils/init: miscinit.c
    src/backend/utils/misc: guc.c postgresql.conf.sample
    src/include    : miscadmin.h

Log message:
    > I can see a couple possible downsides: (a) the library might have some
    > weird behavior across fork boundaries; (b) the additional memory space
    > that has to be duplicated into child processes will cost something per
    > child launch, even if the child never uses it.  But these are only
    > arguments that it might not *always* be a prudent thing to do, not that
    > we shouldn't give the DBA the tool to do it if he wants.  So fire away.

    Here is a patch for the above, including a documentation update. It
    creates a new GUC variable "preload_libraries", that accepts a list in
    the form:

    preload_libraries = '$libdir/mylib1:initfunc,$libdir/mylib2'

    If ":initfunc" is omitted or not found, no initialization function is
    executed, but the library is still preloaded. If "$libdir/mylib" isn't
    found, the postmaster refuses to start.

    In my testing with PL/R, it reduces the first call to a PL/R function
    (after connecting) from almost 2 seconds, down to about 8 ms.

    Joe Conway