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

<strong>Oracle</strong> VLM using shmfs or ramfs
• Buffers are constantly being mapped
in and out of the VLM window.
− If <strong>Oracle</strong> needs to use buffer B, buffer A
needs to be removed from the window to
make room for buffer B.
− If <strong>Oracle</strong> needs to use buffer A again, it will
need to bring it back into the window
SHMFS memory
area
A
8GB
VLM_WINDOW_SIZE
<strong>Oracle</strong> SGA
VLM Window
A
B
2.7GB
B
0
56