Thin Volume metrics

Table 1. Thin volume metrics
Metric	Description
% Hit	The percent of operations that were immediately satisfied by cache
% Miss	The percent of operations that were misses. A miss occurs when the operation cannot be immediately satisfied from cache because the data is not there or the operation has to wait while data is de-staged from cache to disks.
% PowerPath Observed Relative RT	Ratio of PowerPath Response Time to FA Response Time, as a percentage
% Random IO	The percent of I/O operations that were random
% Random Read Hit	Calculated value: 100 * (random read hits per sec/total I/Os per sec).
% Random Read Miss	Calculated value: 100 * (random read misses per sec/total I/Os per sec).
% Random Reads	The percent of I/O that is random reads.
% Random Write Hit	Calculated value: 100 * (random write hits per sec/total I/Os per sec).
% Random Write Miss	Calculated value: 100 * (random write misses per sec/total I/Os per sec).
% Random Writes	The percent of write commands from a host that is not identified as part of a sequential stream.
% Read Hit	The percentage of read operations, performed by the volume, that were immediately satisfied by cache.
% Read Miss	The percentage of read miss operations performed each second by the volume. A miss occurs when the requested read data is not found in cache or the write operation had to wait while data was destaged from cache to the disks.
% Reads	The percentage of I/Os operations that were reads
% Seq Read	Calculated value: 100 * (seq reads per sec/total I/Os per sec).
% Seq Read Hit	The percent of the sequential read operations that were immediately satisfied from cache.
% Seq Read Miss	The percent of the sequential read operations that were misses.
% Seq Write Hit	The percent of the sequential write operations that were immediately satisfied from cache.
% Seq Write Miss	The percent of the sequential write operations that were misses
% Seq Writes	Calculated value: 100*(seq writes per sec/total I/O operations per second).
% Sequential IO	Calculated value: 100 * (total seq I/Os per sec/total I/O operations per second)
% Write Hit	The percentage of write operations, performed by the volume, that were immediately satisfied by cache
% Write Miss	The percent of write miss operations performed each second by the volume. A miss occurs when the write operation had to wait while data was destaged from cache to the disks.
% Writes	The percentage of I/O operations that were writes
Avg IO Size	Calculated value: (HA Kbytes transferred per sec/total IOs per sec)
Avg QOS Delay Per IO	Delay induced by service level management. Calculated value: (Delayed I/O Time /Delayed I/O Count /1000) (applies only to storage systems running PowerMaxOS 5878 or later)
Avg Read Size	Calculated value: (Kbytes read per sec/total reads per sec)
Avg Write Size	Calculated value: (Kbytes written per sec/total writes per sec)
Avg. Write Paced Delay (ms)	Average write paced delay (V3).
BE Prefetched Throughput	The number of MBs prefetched from disk to cache in a second
BE Prefetched Tracks Used/sec	The number of prefetched tracks used each second from the disk directors to the cache
BE Pretetched Tracks/sec	The total prefetched tracks each second from the disk directors to the cache.
BE Read Reqs/sec	The number of read requests each second performed by the disk directors to the cache.
BE Reqs/sec	Number of read/write requests each second performed by the disk directors to cache.
BE Throughput Read	The number of MBs read by the disk directors from the disk each second
BE Throughput Transferred	Calculated value: (MBs read per sec + MBs written per sec)
BE Throughput Written	The number of MBs written to the disk from the disk director each second
BE Write Reqs/sec	The number of write requests each second performed by the disk directors to the cache.
Capacity of RDF Invalid Tracks	The capacity of SRDF invalid tracks
Device Block Size	The block size of the volume
Effective Used Capacity	The effective used capacity
External Read RT	The time that it takes to process a read outside of the system (V4)
External Response Time	The time that it takes to process an I/O request ioutside of the system (V4)
External Write RT	The time that it takes to process a write outside of the system (V4)
Host Hits/sec	The total number of host read I/O and write I/O operations performed each second by the volume that were immediately satisfied by cache.
Host IOs/sec	The total number of host read I/O and write I/O operations performed each second by the volume.
Host Misses/sec	The total number of host read I/O and write I/O operations missed each second by the volume.
Host Read Hits/sec	The total number of host read I/O operations performed each second by the volume that were immediately satisfied by cache.
Host Read Misses/sec	The total number of host read I/O operations missed each second by the volume.
Host Reads/sec	The total number of host read I/O operations performed each second by the volume.
Host Throughput	A cumulative number of host MBs read/writes per second
Host Throughput Read	A cumulative number of host MBs read per second
Host Throughput Written	A cumulative number of host MBs written per second
Host Write Hits/sec	The total number of host write I/O operations performed each second by the volume that were immediately satisfied by cache.
Host Write Misses/sec	The total number of host write I/O operations missed each second by the volume.
Host Writes/sec	The total number of host write I/O operations performed each second by the volume.
Internal Read RT	The internal read response time (V4)
Internal Response Time	The internal response time (V4)
Internal Write RT	The internal write response time (V4)
Max WP Capacity Threshold	The capacity of the maximum number of write-pending slots available
Max WP Threshold	The maximum number of write-pending slots available for the volume
Number of RDF Invalid Tracks	Number of SRDF invalid tracks (V3)
PowerPath Average Response Time	The average response time in milliseconds using PowerPath metrics
PowerPath Observed Delta RT	The difference between PowerPath average response time and device or storage group response time
PowerPath Read Response Time	The read response time from the perspective of PowerPath
PowerPath Write Response Time	The write response time from the perspective of PowerPath
Random Hits/sec	The total number of hits per second that were not sequential
Random IOs/sec	The number of I/Os from a host that is not identified as part of a sequential stream
Random Read Hits/sec	The number of random read I/Os that were satisfied from the cache.
Random Read Misses/sec	The number of random read I/Os that were misses.
Random Reads/sec	The number of read I/O commands from a host that is not identified as part of a sequential stream.
Random Write Hits/sec	The number of random write I/Os that were immediately placed in cache because space was available.
Random Write Misses/sec	The number of random write I/O operations per second that were misses.
Random Writes/sec	The number of write I/O commands from a host that is not identified as part of a sequential stream.
RDF Reads/sec	SRDF reads per second.
RDF Response Time	The SRDF round-trip time - the metric is calculated as follows: SRDF Accumulated Service Time/(SRDF Reads/sec + SRDF Writes/sec) rolled up from the SRDF devices in the group.
RDF Rewrites/sec	SRDF rewrites per second.
RDF Throughput Read	SRDF MBs read per second.
RDF Throughput Written	SRDF MBs written per second
RDF Writes/sec	SRDF writes per second.
RDF/S Write RT	The average time that it took the volume to serve one write I/O
Read Miss RT	The average time a read miss operation was performed by the volume. A miss occurs when the requested data is not found in cache.
Read RT	The calculated average read response time
Response Time	The calculated average response time
Seq IOs/sec	The number of I/O operations performed each second that were sequential.
Seq Read Hits/sec	The number of sequential read operations performed each second by the volume that were immediately satisfied from cache
Seq Read Miss/sec	The number of sequential read operations performed each second by the volume that were misses
Seq Reads/sec	The number of read I/O operations performed each second that were sequential.
Seq Write Hits/sec	The number of sequential write operations performed each second by the volume that were immediately satisfied from cache
Seq Write Misses/sec	The number of sequential write operations performed each second by the volume that were misses
Seq Writes/sec	The number of write I/O operations performed each second that were sequential.
Slot Collisions/sec	Write misses/sec due to the desired cache slot being locked by another request (Task 7 + Task 11) (V4)
Slot Collisions RT	The average response time of a write miss due to the desired cache slot being locked by another request (Task 7 + Task 11) (V4)
Total Capacity	The total capacity of the thin volume (GB)
Total Response Time	The total response time
VAAI Total Command Count	Number of VAAI commands that were issued
VAAI Total Time	VAAI total time
VAAI Unmap Command Count	Number of VAAI unmap commands that were issued.
VAAI Unmap MB	VAAI Unmap MB (V3)
VAAI Unmap Throughput	VAAI Unmap throughput
VAAI Write Same Command Count	Number of VAAI write same commands issued.
VAAI Write Same MB	VAAI Write Same MB (V3)
VAAI Write Same Throughput	VAAI Write Same throughput
VAAI XCopy Command Count	Number of VAAI XCopy commands issued
VAAI XCopy MB	VAAI XCopy MB (V3)
VAAI XCopy Throughput	VAAI XCopy throughput
WP Count	The number of tracks in write pending mode for the volume.
WP Used Capacity	WP used capacity
Write Miss RT	The average time a write miss operation was performed by the volume. A miss occurs when the write operation has to wait while data is destaged from cache to disks.
Write Paced Delay (ms)	Write paced delay (V3).
Write RT	The calculated average write response time

% Hit

The percent of operations that were immediately satisfied by cache

% Miss

The percent of operations that were misses. A miss occurs when the operation cannot be immediately satisfied from cache because the data is not there or the operation has to wait while data is de-staged from cache to disks.

% PowerPath Observed Relative RT

Ratio of PowerPath Response Time to FA Response Time, as a percentage

% Random IO

The percent of I/O operations that were random

% Random Read Hit

Calculated value: 100 * (random read hits per sec/total I/Os per sec).

% Random Read Miss

Calculated value: 100 * (random read misses per sec/total I/Os per sec).

% Random Reads

The percent of I/O that is random reads.

% Random Write Hit

Calculated value: 100 * (random write hits per sec/total I/Os per sec).

% Random Write Miss

Calculated value: 100 * (random write misses per sec/total I/Os per sec).

% Random Writes

The percent of write commands from a host that is not identified as part of a sequential stream.

% Read Hit

The percentage of read operations, performed by the volume, that were immediately satisfied by cache.

% Read Miss

The percentage of read miss operations performed each second by the volume. A miss occurs when the requested read data is not found in cache or the write operation had to wait while data was destaged from cache to the disks.

% Reads

The percentage of I/Os operations that were reads

% Seq Read

Calculated value: 100 * (seq reads per sec/total I/Os per sec).

% Seq Read Hit

The percent of the sequential read operations that were immediately satisfied from cache.

% Seq Read Miss

The percent of the sequential read operations that were misses.

% Seq Write Hit

The percent of the sequential write operations that were immediately satisfied from cache.

% Seq Write Miss

The percent of the sequential write operations that were misses

% Seq Writes

Calculated value: 100*(seq writes per sec/total I/O operations per second).

% Sequential IO

Calculated value: 100 * (total seq I/Os per sec/total I/O operations per second)

% Write Hit

The percentage of write operations, performed by the volume, that were immediately satisfied by cache

% Write Miss

The percent of write miss operations performed each second by the volume. A miss occurs when the write operation had to wait while data was destaged from cache to the disks.

% Writes

The percentage of I/O operations that were writes

Avg IO Size

Calculated value: (HA Kbytes transferred per sec/total IOs per sec)

Avg QOS Delay Per IO

Delay induced by service level management. Calculated value: (Delayed I/O Time /Delayed I/O Count /1000) (applies only to storage systems running PowerMaxOS 5878 or later)

Avg Read Size

Calculated value: (Kbytes read per sec/total reads per sec)

Avg Write Size

Calculated value: (Kbytes written per sec/total writes per sec)

Avg. Write Paced Delay (ms)

Average write paced delay (V3).

BE Prefetched Throughput

The number of MBs prefetched from disk to cache in a second

BE Prefetched Tracks Used/sec

The number of prefetched tracks used each second from the disk directors to the cache

BE Pretetched Tracks/sec

The total prefetched tracks each second from the disk directors to the cache.

BE Read Reqs/sec

The number of read requests each second performed by the disk directors to the cache.

BE Reqs/sec

Number of read/write requests each second performed by the disk directors to cache.

BE Throughput Read

The number of MBs read by the disk directors from the disk each second

BE Throughput Transferred

Calculated value: (MBs read per sec + MBs written per sec)

BE Throughput Written

The number of MBs written to the disk from the disk director each second

BE Write Reqs/sec

The number of write requests each second performed by the disk directors to the cache.

Capacity of RDF Invalid Tracks

The capacity of SRDF invalid tracks

Device Block Size

The block size of the volume

Effective Used Capacity

The effective used capacity

External Read RT

The time that it takes to process a read outside of the system (V4)

External Response Time

The time that it takes to process an I/O request ioutside of the system (V4)

External Write RT

The time that it takes to process a write outside of the system (V4)

Host Hits/sec

The total number of host read I/O and write I/O operations performed each second by the volume that were immediately satisfied by cache.

Host IOs/sec

The total number of host read I/O and write I/O operations performed each second by the volume.

Host Misses/sec

The total number of host read I/O and write I/O operations missed each second by the volume.

Host Read Hits/sec

The total number of host read I/O operations performed each second by the volume that were immediately satisfied by cache.

Host Read Misses/sec

The total number of host read I/O operations missed each second by the volume.

Host Reads/sec

The total number of host read I/O operations performed each second by the volume.

Host Throughput

A cumulative number of host MBs read/writes per second

Host Throughput Read

A cumulative number of host MBs read per second

Host Throughput Written

A cumulative number of host MBs written per second

Host Write Hits/sec

The total number of host write I/O operations performed each second by the volume that were immediately satisfied by cache.

Host Write Misses/sec

The total number of host write I/O operations missed each second by the volume.

Host Writes/sec

The total number of host write I/O operations performed each second by the volume.

Internal Read RT

The internal read response time (V4)

Internal Response Time

The internal response time (V4)

Internal Write RT

The internal write response time (V4)

Max WP Capacity Threshold

The capacity of the maximum number of write-pending slots available

Max WP Threshold

The maximum number of write-pending slots available for the volume

Number of RDF Invalid Tracks

Number of SRDF invalid tracks (V3)

PowerPath Average Response Time

The average response time in milliseconds using PowerPath metrics

PowerPath Observed Delta RT

The difference between PowerPath average response time and device or storage group response time

PowerPath Read Response Time

The read response time from the perspective of PowerPath

PowerPath Write Response Time

The write response time from the perspective of PowerPath

Random Hits/sec

The total number of hits per second that were not sequential

Random IOs/sec

The number of I/Os from a host that is not identified as part of a sequential stream

Random Read Hits/sec

The number of random read I/Os that were satisfied from the cache.

Random Read Misses/sec

The number of random read I/Os that were misses.

Random Reads/sec

The number of read I/O commands from a host that is not identified as part of a sequential stream.

Random Write Hits/sec

The number of random write I/Os that were immediately placed in cache because space was available.

Random Write Misses/sec

The number of random write I/O operations per second that were misses.

Random Writes/sec

The number of write I/O commands from a host that is not identified as part of a sequential stream.

RDF Reads/sec

SRDF reads per second.

RDF Response Time

The SRDF round-trip time - the metric is calculated as follows: SRDF Accumulated Service Time/(SRDF Reads/sec + SRDF Writes/sec) rolled up from the SRDF devices in the group.

RDF Rewrites/sec

SRDF rewrites per second.

RDF Throughput Read

SRDF MBs read per second.

RDF Throughput Written

SRDF MBs written per second

RDF Writes/sec

SRDF writes per second.

RDF/S Write RT

The average time that it took the volume to serve one write I/O

Read Miss RT

The average time a read miss operation was performed by the volume. A miss occurs when the requested data is not found in cache.

Read RT

The calculated average read response time

Response Time

The calculated average response time

Seq IOs/sec

The number of I/O operations performed each second that were sequential.

Seq Read Hits/sec

The number of sequential read operations performed each second by the volume that were immediately satisfied from cache

Seq Read Miss/sec

The number of sequential read operations performed each second by the volume that were misses

Seq Reads/sec

The number of read I/O operations performed each second that were sequential.

Seq Write Hits/sec

The number of sequential write operations performed each second by the volume that were immediately satisfied from cache

Seq Write Misses/sec

The number of sequential write operations performed each second by the volume that were misses

Seq Writes/sec

The number of write I/O operations performed each second that were sequential.

Slot Collisions/sec

Write misses/sec due to the desired cache slot being locked by another request (Task 7 + Task 11) (V4)

Slot Collisions RT

The average response time of a write miss due to the desired cache slot being locked by another request (Task 7 + Task 11) (V4)

Total Capacity

The total capacity of the thin volume (GB)

Total Response Time

The total response time

VAAI Total Command Count

Number of VAAI commands that were issued

VAAI Total Time

VAAI total time

VAAI Unmap Command Count

Number of VAAI unmap commands that were issued.

VAAI Unmap MB

VAAI Unmap MB (V3)

VAAI Unmap Throughput

VAAI Unmap throughput

VAAI Write Same Command Count

Number of VAAI write same commands issued.

VAAI Write Same MB

VAAI Write Same MB (V3)

VAAI Write Same Throughput

VAAI Write Same throughput

VAAI XCopy Command Count

Number of VAAI XCopy commands issued

VAAI XCopy MB

VAAI XCopy MB (V3)

VAAI XCopy Throughput

VAAI XCopy throughput

WP Count

The number of tracks in write pending mode for the volume.

WP Used Capacity

WP used capacity

Write Miss RT

The average time a write miss operation was performed by the volume. A miss occurs when the write operation has to wait while data is destaged from cache to disks.

Write Paced Delay (ms)

Write paced delay (V3).

Write RT

The calculated average write response time