Performance statistics for shared memory

• Statistics about the shared memory pool, such as:
  • Size of the shared memory pool
  • Total amount of memory that is overcommitted
  • Total amount of logical memory that is assigned to the shared memory partitions
  • Total amount of I/O entitled memory that is assigned to the shared memory partitions
  • Total amount of physical memory that the shared memory partitions currently use for their I/O devices
  • Amount of memory from the shared memory pool that the hypervisor uses to manage the shared memory partitions
  • The time it takes, in microseconds, for data to be written to the shared memory pool from the paging space device
• Statistics about the shared memory partitions, such as:
  • Amount of logical memory assigned to the shared memory partition
  • Amount of physical memory from the shared memory pool that is allocated to the shared memory partition
  • Amount of memory that is overcommitted
  • I/O entitled memory assigned to the shared memory partition
  • Amount of physical memory that the shared memory partition currently uses for its I/O devices
  • Memory weight of the shared memory partition

Use the IVM lslparutil command to view shared memory statistics in the Integrated Virtualization Manager.

• Statistics about the shared memory pool, such as:
  • Size of the shared memory pool
  • Total amount of logical memory that is assigned to the active shared memory partitions
  • Total amount of I/O entitled memory that is assigned to the active shared memory partitions
  • Total amount of physical memory that the active shared memory partitions currently use for their I/O devices
  • The total number of page faults that occurred since the shared memory pool was created or since the managed system was restarted, whichever is most recent
  • Total time, in milliseconds, that the processors waited for page faults to be resolved since the shared memory pool was created or since the managed system was restarted, whichever is most recent
  • Amount of physical memory in the shared memory pool that is reserved for the server firmware
• Statistics about the shared memory partitions, such as:
  • Amount of physical memory from the shared memory pool that is allocated to the shared memory partition
  • I/O entitled memory assigned to the shared memory partition
  • Amount of physical memory that the shared memory partition currently uses for its I/O devices
  • Memory weight of the shared memory partition

Use Collection Services to view shared memory statistics in IBM i.

• Statistics about the shared memory pool, such as:
  • Total number of page faults for all of the shared memory partitions
  • Total time, in milliseconds, that the processors waited for page faults to be resolved
  • Total physical memory, in bytes, that is assigned to the shared memory pool
  • Sum of the logical memory, in bytes, that is assigned to all of the shared memory partitions that are active
  • Sum of the I/O entitled memory, in bytes, that is assigned to all of the shared memory partitions that are active
  • Sum of the physical memory, in bytes, that the shared memory partitions that are active currently use for their I/O devices
• Statistics about the shared memory partition, such as:
  • Memory weight of the shared memory partition
  • Amount of physical memory, in bytes, from the shared memory pool that is currently used by the shared memory partition
  • Number of times that the shared memory partition waited for a page fault
  • The time, in milliseconds, that the shared memory partition waited for page faults to be resolved
  • Maximum amount of memory, in bytes, that the shared memory partition can assign to data areas that are shared between the operating system and the server firmware
  • I/O entitled memory assigned to the shared memory partition
  • Minimum amount of physical memory, in bytes, required for all of the configured I/O devices to operate
  • Optimal amount of physical memory, in bytes, required for I/O devices to maximize throughput performance
  • Amount of physical memory, in bytes, that the shared memory partition currently uses for its I/O devices
  • Highest amount of physical memory, in bytes, that the shared memory partition has used for its I/O devices since the last time the shared memory partition was activated or since the last time the memory statistics were reset, whichever is most recent
  • Number of delayed I/O operations since the last time the shared memory partition was activated

View memory statistics for Linux in the sysfs file system as follows:

• Shared memory partition data: cat /proc/ppc64/lparcfg
• Virtual I/O bus attributes: /sys/bus/vio/ directory.
• Virtual I/O device attributes: /sys/bus/vio/devices/ directory. This directory has a subdirectory for each device. Look in the subdirectory for each device to see the virtual I/O device statistics for each device.
• Shared Memory statistics: amsstat (included in powerpc-utils)
• Shared Memory graphical monitoring: amsvis (included in powerpc-utils-python)

• Statistics about the shared memory partition:
  • I/O entitled memory set for the shared memory partition
  • Memory weight of the shared memory partition
  • Amount of physical memory allocated to the shared memory partition
  • Size of the shared memory pool to which the shared memory partition belongs
  • Frequency that data is written to the shared memory pool from the paging space device
  • The time it takes, in microseconds, for data to be written to the shared memory pool from the paging space device
• Statistics about the virtual I/O bus, such as the highest amount of physical memory the shared memory partition has ever used for its I/O devices.
• Statistics about the virtual I/O devices, such as the frequency that the device tried to map a page to perform an I/O operation and was unable to obtain sufficient memory. In this situation, the attempt fails and delays the I/O operation.
• Statistics about the tools:
  • The packages powerpc-utils and powerpc-utils-python are userspace packages.
  • The amsstat script can be run from a Linux logical partition to display shared memory statistics associated with the logical partition.
  • The amsvis tool is a python based graphical tool that displays similar information in a graphical manner. This tool is capable of aggregating data from multiple Linux shared memory logical partitions to obtain a picture of cross logical partition performance of shared memory Linux logical partitions.