2 service time histogram buckets, 3 io size histogram buckets, Service time histogram buckets – HP 3PAR System Reporter Software User Manual

Page 328: Io size histogram buckets, Service time histogram, Buckets

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10.36

The Sample Data and Inventory Tables

3PAR System Reporter User’s Guide

System Reporter 2.8

10.4.9.2 Service Time Histogram Buckets

The service time range corresponding to each of the rhist and whist buckets depends on the

version of the InFormOS (os_rev column in the system table, see

The system Table

on

page 10.4). For os_rev prior to 2.2.2, the nth bucket (rhistn and whistn) correspond to service

times from the previous bucket to (2

n

*4.096/mhz) millisec where mhz is the mhz column in the

system_3 table (see

The system Table

on page 10.4). This means that service time histograms

from systems with different CPU frequencies could not be correctly aggregated. Beginning

with the 2.2.2 release, the buckets were made independent of the CPU frequency, and the nth

bucket (rhistn and whistn) corresponds to service times from the previous bucket to (2

n-7

)

millisec.

10.4.9.3 IO Size Histogram Buckets

There are16 IO Size buckets correspond IO sizes 512 bytes to 16MiBytes. The nth bucket holds

the count for IO Sizes from the previous bucket’s max size to 512 * 2

n

bytes.

Total IO Size

(KBytes)

CASE WHEN (d_rcount + d_wcount) > 0 THEN (d_rbytes +

d_wbytes) / ((d_rcount + d_wcount) * 1000.0) ELSE 0 END

Queue length

CASE WHEN qlen > 0 THEN qlen ELSE 0 END

The check for qlen > 0 is because qlen < 0 indicates that qlen is

invalid for that sample.

Busy%

AVG(CASE WHEN ((d_now > 0) AND (d_busy < busy)) THEN

(d_busy * 100.0/d_now) ELSE 0 END)

Table 10-20. Common Performance Metrics for a Sample Row

Metric

SQL Expression

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