This outlines how to increase the number of shared memory buffers

supported by BSD/OS. By default, only 4MB of shared memory is supported

by BSDI.

This outlines modifications to BSD/OS for running PostgreSQL:

Keep in mind that shared memory is not pageable. It is locked in RAM.

1) How to increase resource limits

2) How to increase the number of shared memory buffers

Bruce Momjian (pgman@candle.pha.pa.us)

Bruce Momjian (pgman@candle.pha.pa.us) 2000-06-09

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Increase SHMMAXPGS by 1024 for every additional 4MB of shared

memory:

1) To increase the amount of malloc'ed memory and files opened by

PostgreSQL, add this:

:datasize-cur=600M:\

:openfiles-cur=256:

to your /etc/login.conf file.

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2a) By default, only 4MB of shared memory is supported by BSDI. Keep in

mind that shared memory is not pageable. It is locked in RAM.

To increase the number of buffers supported by the postmaseter, increase

SHMMAXPGS by 1024 for every additional 4MB of shared memory:

/sys/sys/shm.h:69:#define SHMMAXPGS 1024 /* max hardware pages...

The default setting of 1024 is for a maximum of 4MB of shared memory.

For those running 4.1 or later, just recompile the kernel and reboot.

For those running earlier releases,there are more steps outlined below.

For those running earlier releases,see step 2b.

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Usebpatch to find the sysptsize value for the current kernel.

This is computed dynamically at bootup.

2b) For 4.01 and earlier, usebpatch to find the sysptsize value for

the current kernel.This is computed dynamically at bootup.

$ bpatch -r sysptsize

0x9 = 9