The previous method worked off the full virtual address space, not just
the shared memory usage.
Author: Tsunakawa, Takayuki <tsunakawa.takay@jp.fujitsu.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Vasundhar Boddapati <bvasundhar@gmail.com>
the kernel setting <varname>vm.nr_hugepages</varname>. To estimate the
number of huge pages needed, start <productname>PostgreSQL</productname>
without huge pages enabled and check the
- postmaster's <varname>VmPeak</varname> value, as well as the system's
+ postmaster's anonymous shared memory segment size, as well as the system's
huge page size, using the <filename>/proc</filename> file system. This might
look like:
<programlisting>
$ <userinput>head -1 $PGDATA/postmaster.pid</userinput>
4170
-$ <userinput>grep ^VmPeak /proc/4170/status</userinput>
-VmPeak: 6490428 kB
+$ <userinput>pmap 4170 | awk '/rw-s/ && /zero/ {print $2}'</userinput>
+6490428K
$ <userinput>grep ^Hugepagesize /proc/meminfo</userinput>
Hugepagesize: 2048 kB
</programlisting>