13 Feb/14 - Trick: Solaris CoolThread CPU Thread RPF
The ORACLE T-class of systems (CoolThreads) are SPARC systems that have Chip Multithreading technology (CMT) provided by UltraSPARC T1, T2, or T2 Plus processors. Virtualization can be done through Solaris Containers and Logical Domains (Ldoms). In case of Logical Domains it is quite easy to change the amount of logical CPU's (processor threads or vcpu's) allocated to a domain via, for example, the command “ldm add-vcpu 4 ”. As such it is possible that during the life time of an LDOM the number of processor threads changes.
In order to analyze the CPU capacity of such an LDOM it would be great to have something like a Relative Performance Factor related to such a thread. This little document describes a way to accomplish this by using a User Parameter Agent, running on each LDOM, that loads a thread related RPF value each minute which then can be used to calculate CPU capacity via a derived table in ITSAR.