Statistic Collection For Volumes That Are Used; Relationships For Individual Nodes; Statistic Collection For Node Ports - IBM Storwize V7000 Unified Problem Determination Manual

Table 58. Statistic collection for volumes for individual nodes (continued)
Indicates the cumulative number of volume read operations processed (since
ro
the node has been running).
wb Indicates the cumulative number of blocks of data written (since the node
has been running).
wl Indicates the cumulative write response time in milliseconds for each
volume. The cumulative response time for volume writes is calculated by
starting a timer when a SCSI write command is received and stopped when
the command completes successfully. The elapsed time is added to the
cumulative counter.
wlw Indicates the worst write response time in microseconds for each volume
since the last time statistics were collected. This value is reset to zero after
each statistics collection sample.
wo Indicates the cumulative number of volume write operations processed (since
the node has been running).
Indicates the cumulative number of volume write operations that are not
wou
aligned on a 4K boundary.
xl Indicates the cumulative read and write data transfer response time in
milliseconds for each volume since the last time the node was reset. When
this statistic is viewed for multiple volumes and with other statistics, it can
indicate if the latency is caused by the host, fabric, or the Storwize V7000
Unified.
Table 59 describes the VDisk information related to Metro Mirror or Global Mirror
relationships that is reported for individual nodes.
Table 59. Statistic collection for volumes that are used in Metro Mirror and Global Mirror

relationships for individual nodes

Statistic Description
name
gwl Indicates cumulative secondary write latency in milliseconds. This statistic
accumulates the cumulative secondary write latency for each volume. You
can calculate the amount of time to recovery from a failure based on this
statistic and the gws statistics.
gwo Indicates the total number of overlapping volume writes. An overlapping
write is when the logical block address (LBA) range of write request collides
with another outstanding request to the same LBA range and the write
request is still outstanding to the secondary site.
gwot Indicates the total number of fixed or unfixed overlapping writes. When all
nodes in all clusters are running Storwize V7000 Unified version 4.3.1, this
records the total number of write I/O requests received by the Global Mirror
feature on the primary that have overlapped. When any nodes in either
cluster are running Storwize V7000 Unified versions earlier than 4.3.1, this
value does not increment.
gws Indicates the total number of write requests that have been issued to the
secondary site.
Table 60 describes the port information that is reported for individual nodes
Table 60. Statistic collection for node ports
Statistic Description
name
Chapter 5. Control enclosure
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