See Ravi Talashikar's blog for an explanation of CPU vs core utilization on CMT architectures such as the T1000: http://blogs.sun.com/travi/entry/ultrasparc_t1_utilization_explained
- Steve On 09/30/08 15:18, Elad Lahav wrote: > I'm looking into the performance of a simple, single-threaded, TCP server on > a T1000. > According to mpstat, the strand running the server is about 50% idle. > However, performance > counters suggest that it is executing about 230 million instructions per > second, which, > from my experience thus far, is pretty much the limit of a single-threaded > application. > Roughly the same numbers are reported for the strand handling the interrupts > (the two are > on different cores, so there is no competition for shared resources). The NIC > is reading > at 700Mbps, so the network is not the bottleneck. > > I'm having a hard time putting all of this information together, as there is > no clear > bottleneck. Also, I think there is a more general issue here: how can one > interpret > per-strand mpstat numbers, as the resources available to a strand change > dynamically with > the load on a core? > > --Elad > > _______________________________________________ > perf-discuss mailing list > perf-discuss@opensolaris.org _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org
