HP Caliper User's Guide

cpubus Event Set
Available only on Itanium 2 and dual-core Itanium 2 systems.
The cpubus event set provides information on the demand that a specific CPU presents
to the central electronics complex (CEC), the chip set surrounding the CPU, and the
demand the CPU experiences due to the CEC traffic initiated by other CPUs or I/O
components in the system.
If you use this event set, the default is to make the measurements irrespective of CPU
operating state (that is, user, system, or interrupt states). By default, the idle state is
not included in the measurement. You can use command-line options to limit the scope
of the measurement. Specifically, you can:
• Limit measurement to a specific privilege level: -m
event_set[:all|user|kernel]
• Include idle: --exclude-idle False
• Exclude the interruption state: --measure-on-interrupts off
• Only measure the interruption state: --measure-on-interrupts only
Metrics Available from this Measurement
The following metrics are available from this event set. These descriptions do not take
into account any command-line options you might use.
The metrics are all per-second metrics. The metrics are:
• Imiss
This is the instruction demand fetch misses per second produced by the local
processor. This does not include instruction prefetch requests that miss the L3
cache.
• Dmiss
This is the data (load and store) misses per second produced by the local processor.
• C2C
This is the number of implicit writebacks (C2C) per second that occur as a result
of data cache misses produced by the local processor referenced data that is in the
modified state in a remote cache.
• WB
This is the number of writebacks per second that occur in the local processors cache
in response to data cache misses replacing modified lines. It does not include
implicit writebacks that are initiated in response to remote coherence requests.
• Ccast Out
Counts the number of writeback memory write transactions (BWL writes due to
M-state line writebacks and coalesced writes) per second. Only counts zero-byte
transactions with the writeback attribute (clean castouts) from the local CPU.
cpubus Event Set 309