I/O Statistics Help
Statistics Overview
ServerNet SAN I/O consists of read and write transactions (operations)
initiated by each ServerNet PCI Adapter
(SPA) in the cluster. Each read or write operation by a
given SPA typically results in the transfer of some number of bytes of
data (read) from or (written) to a destination SPA. With the I/O Statistics
view, you can select a SPA in the cluster, then view the read/write operation
counts and the read/write byte counts:
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Initiated by that SPA to all other SPAs in the cluster.
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Initiated by all other SPAs in the cluster to that SPA.
The ServerNet SAN operation and byte count statistics for a given SPA are
cleared to zero when the associated node is booted or when the ServerNet
SAN path being used by the SPA is switched (between the X and Y ports).
Therefore, the non-zero operation and byte counts appear in the column
(X Count or Y Count) of the active path and reflect the magnitude of the
traffic since the last path switch or node boot.
NOTE: The operation and byte count numbers are approximate.
Viewing Statistics
The I/O statistics appear in two panes:
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I/O Statistics for Paths From SPA N (where N = SPA number), which
shows operation and byte counts initiated by the selected SPA to all other
SPAs in the cluster.
-
I/O Statistics for Paths To SPA N, which shows operation and byte
counts initiated by all other SPAs in the cluster to the selected SPA.
Associated with each of these two panes is a SPA choice box used to select
the SPA for which the I/O statistics are retrieved. The amount of vertical
space allotted to each pane within the NonStop Cluster Management Suite
(NCMS) window can be adjusted by dragging
the horizontal line between the panes up or down or by clicking the arrowheads
on the line.
Procedure
For either pane, view the I/O statistics as follows:
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Select the SPA that you want I/O statistics for with the SPA choice box
next to the chosen pane.
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In the chosen pane, click the plus (+) sign to the left of the desired
SPA pair to see the associated I/O statistics. For example, if SPA 2 was
selected in Step 1, the [2, 1] SPA pair can be expanded to see the operation
and byte counts initiated by SPA 2 to SPA 1.
-
Expand all SPA pairs (click on + signs) as needed.
With the I/O statistics for a SPA pair displayed, they can be collapsed
and hidden by clicking on the negative (-) sign to the left of the pair.