Type: integer
Default: 1024 (8MB)
Min: 100 (800kB)
Max: 1073741823 (8589934584kB)
Unit: 8kB
Context: user
Restart: false

Sets the maximum amount of memory used for temporary buffers within each database session. These are session-local buffers used only for access to temporary tables. If this value is specified without units, it is taken as blocks, that is BLCKSZ bytes, typically 8kB. The default is eight megabytes (8MB). (If BLCKSZ is not 8kB, the default value scales proportionally to it.) This setting can be changed within individual sessions, but only before the first use of temporary tables within the session; subsequent attempts to change the value will have no effect on that session.

A session will allocate temporary buffers as needed up to the limit given by temp_buffers. The cost of setting a large value in sessions that do not actually need many temporary buffers is only a buffer descriptor, or about 64 bytes, per increment in temp_buffers. However if a buffer is actually used an additional 8192 bytes will be consumed for it (or in general, BLCKSZ bytes).

Recommendations

Currently used only for holding temporary tables in memory. If your application requires heavy use of temporary tables (many proprietary reporting engines do) then you might want to increase this substantially. However, be careful because this is non-shared RAM which is allocated per session. Otherwise, the default is fine.

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