Topics: AIX, SSA, Storage

SSA Fast Write

For high-disk performance systems, such as SSA, it is wise to enable the fast write on the disks. To check which disks are fast write enabled, type:

# smitty ssafastw
Fast write needs cache memory on the SSA adapter. Check your amount of cache memory on the SSA adapter:
# lscfg -vl ssax
Where 'x' is the number of your SSA adapter. 128MB of SDRAM will suffice. Having 128MB of SDRAM memory makes sure you can use the full 32MB of cache memory.

To enable the fast write the disk must not be in use. So either the volume groups are varied offline, or the disk is taken out of the volume group. Use the following command to enable the fast write cache:
# smitty chgssardsk

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