mirror of
https://github.com/postgres/postgres.git
synced 2025-07-30 11:03:19 +03:00
Update faq's.
This commit is contained in:
31
doc/FAQ_BSDI
Normal file
31
doc/FAQ_BSDI
Normal file
@ -0,0 +1,31 @@
|
||||
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.
|
||||
|
||||
Bruce Momjian (pgman@candle.pha.pa.us)
|
||||
|
||||
---------------------------------------------------------------------------
|
||||
|
||||
First, 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.
|
||||
|
||||
Second, use bpatch to find the sysptsize value for the current kernel.
|
||||
This is computed dynamically at bootup.
|
||||
|
||||
$ bpatch -r sysptsize
|
||||
0x9 = 9
|
||||
|
||||
Next, change SYSPTSIZE to a hard-coded value. Use the bpatch value,
|
||||
plus add 1 for every additional 4MB of shared memory you desire.
|
||||
|
||||
/sys/i386/i386/i386_param.c:28:#define SYSPTSIZE 0 /* dynamically...
|
||||
|
||||
sysptsize can not be changed by sysctl on the fly.
|
||||
|
||||
This should clearly be easier to do on BSDI. I will add a BSDI FAQ for
|
||||
PostgreSQL to cover this. One downside is that shared memory is not
|
||||
pageable. It is locked in RAM.
|
Reference in New Issue
Block a user