Maximum amount of memory (in Kbyte) to use for one buffer. When this limit is reached allocating extra memory for a buffer will cause other memory to be freed. The maximum usable value is about 2000000. Use this to work without a limit. The value is ignored when 'swapfile' is off. Also see 'maxmemtot'.

(default between 256 to 5120 (system dependent) or half the amount of memory available)