Processor set defined as above consists of 4 cpus. Total cpu on this box are 16. My application has a single RTT running a busy loop. I am assigning 2 threads for RTGC, but when I look at summary<pid>.txt generated by TSV, it shows 15 RTGC threads one named RTGC Thread#0 and all other are Gang worker#<i> (RTGC Threads). Should not only two RTGC threads should be running.
I have 4 cpus assigned for running real time threads and I expect maximum 3 real time threads at any point of time(1 application and two RTGC threads), I am keeping actual RTT count lower than cpus available to make sure that no RTT should hop cpus but tsv summary suggests that there are 1-5 hops happening in case of application real time thread. Application thread is running a loop which do exactly same calculations in each iteration and measure time taken by this calculation. When I plot calculation time i see few peaks which are around 120 micro seconds higher than median of 137 micro seconds. Also near these peaks there is some jitter in range of ~50 micros above median.
I also tried running same benchmark with 8 cores but results are still same. No improvements in terms of performance. If I change application thread logic to create some big objects instead of dping calculations jitters frequency and magnitude both increases.