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35 lines
1.2 KiB
Plaintext
35 lines
1.2 KiB
Plaintext
This outlines how to increase the number of shared memory buffers
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supported by BSD/OS. By default, only 4MB of shared memory is supported
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by BSDI.
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Keep in mind that shared memory is not pageable. It is locked in RAM.
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Bruce Momjian (pgman@candle.pha.pa.us)
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---------------------------------------------------------------------------
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Increase SHMMAXPGS by 1024 for every additional 4MB of shared
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memory:
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/sys/sys/shm.h:69:#define SHMMAXPGS 1024 /* max hardware pages...
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The default setting of 1024 is for a maximum of 4MB of shared memory.
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For those running 4.1 or later, just recompile the kernel and reboot.
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For those running earlier releases, there are more steps outlined below.
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---------------------------------------------------------------------------
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Use bpatch to find the sysptsize value for the current kernel.
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This is computed dynamically at bootup.
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$ bpatch -r sysptsize
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0x9 = 9
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Next, change SYSPTSIZE to a hard-coded value. Use the bpatch value,
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plus add 1 for every additional 4MB of shared memory you desire.
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/sys/i386/i386/i386_param.c:28:#define SYSPTSIZE 0 /* dynamically...
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sysptsize can not be changed by sysctl on the fly.
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