Oracle RAC on RedHat Linux Best Practice guide and ... - OpenMPE

IA-32: large memory pages
(bigpages)
• Have the kernel allocate a pool of bigpage memory
• Add “bigpages=xxxxMB” to the kernel boot line in
grub.conf or lilo.conf.
• Tell the kernel to use the bigpage pool for shared
memory allocations
− [root]# echo 2 > /proc/sys/kernel/shm-user-bigpages
• Size the bigpage memory pool to be only as large as
needed because it is only used for shared memory
allocations
• Unused memory in the bigpage pool will be not be
available for general use, even if the system is
swapping.
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