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Abstract
The effects of PP size on LVM performance.
Content
If the PP SIZE is too small for a large disk, the large number of physical partitions may slow LVM operations.
PP SIZE is set at the time of volume group creation using the '-s' flag. If the PP SIZE is small and the disk is large, there could be an unmanageable number of physical partitions.
For example, a 1TB disk with PP SIZE 4MB, will have 262,144 physical partitions. The memory needed to account for that many partitions could result in slow LVM operations.
It is recommended to choose a PP SIZE that is appropriate for the disk size. For a 1TB disk, a PP SIZE of 1024 (1GB), will result in 1024 partitions.
Your application or database vendor may have a recommended PP size. So, it is advised to also check your configuration documentation when choosing a PP size.
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Document Information
Modified date:
03 October 2019
UID
ibm10713461