Table 62. Cache statistics collection for volumes and volume copies (continued)
Statistic Acronym
Statistics for
volume
cache
Statistics for
volume
copy cache
Statistics for
volume
cache
partition
Statistics for
volume
copy cache
partition
Statistics for
the Node
Overall
Cache
Cache
statistics for
mdisks
Units and
state
Buffer Queue
Time
bpt Yes Average µs,
non-
cumulative
Hardening
Rights Queue
Time
hrpt Yes Average µs,
non-
cumulative
Note: Any statistic with a name av, mx, mn, and cn is not cumulative. These
statistics reset every statistics interval. For example, if the statistic does not have a
name with name av, mx, mn, and cn, and it is an Ios or count, it will be a field
containing a total number.
v The term pages means in units of 4096 bytes per page.
v The term sectors means in units of 512 bytes per sector.
v The term µs means microseconds.
v Non-cumulative means totals since the previous statistics collection interval.
v Snapshot means the value at the end of the statistics interval (rather than an
average across the interval or a peak within the interval).
Table 63 describes the statistic collection for volume cache per individual nodes.
Table 63. Statistic collection for volume cache per individual nodes. This table describes the
volume cache information that is reported for individual nodes.
Statistic
name
Description
cm Indicates the number of sectors of modified or dirty data that are held in the
cache.
ctd Indicates the total number of cache destages that were initiated writes,
submitted to other components as a result of a volume cache flush or destage
operation.
ctds Indicates the total number of sectors that are written for cache-initiated track
writes.
ctp Indicates the number of track stages that are initiated by the cache that are
prestage reads.
ctps Indicates the total number of staged sectors that are initiated by the cache.
ctrh Indicates the number of total track read-cache hits on prestage or
non-prestage data. For example, a single read that spans two tracks where
only one of the tracks obtained a total cache hit, is counted as one track
read-cache hit.
ctrhp Indicates the number of track reads received from other components, treated
as cache hits on any prestaged data. For example, if a single read spans two
tracks where only one of the tracks obtained a total cache hit on prestaged
data, it is counted as one track read for the prestaged data. A cache hit that
obtains a partial hit on prestage and non-prestage data still contributes to this
value.
ctrhps Indicates the total number of sectors that are read for reads received from
other components that obtained cache hits on any prestaged data.
Chapter 5. Control enclosure 223
To Next Page
Loading...
Need help?
General
