When preparing for the test, have a look at the very interesting
cpustat/cputrack. Without this you won't really be able to judge on the
cpu usage. Classical tools like sar/vmstat/prstat easily lead to wrong
results (the amount of work a single strand [hardware thread] is able to
do is not fixed. It really shares the core with the other strands. If
they stall, it will execute on every cycle, if all 4 strands are busy
each one will only execute on every 4th cycle. So the cpu power
available to a strand is dynamic, but tools like prstat are not able to
show that.
For memory bus usage busstat is the way to go.
If you need more info, you could start an off topic thread or mail me
directly.
Rainer
Jeff Genender wrote:
Yep...each core will handle 4 hardware threads. It was built for
multiple threads and a JVM (multithreaded of course) is made for this
box. For an appserver under load, I think the numbers should be
impressive on this box.
The cool thing about this machine is, each core is viewed as 4 cpus.
That means this box looks like it has 16 CPUs running (4 cores x 4
hardware threads)!
I can't wait to pound on this and see what it can do. I am going to
have T2000->T2000 trials going on to maximize the throughput for CPU.
They come with 4 1 Ghz Ethernet ports each, so I am going to pipe these
up and hopefully there will be zero bottleneck on IO.
