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run/cpu_quota: raise measurement precision further 

Three things were done:

* Timouts are measured in an asynchronous way to be able to start counters
  after the potentially expensive RPC that starts the timeout.
* Timeouts were increased from 45 and 15 seconds to 60 and 20 seconds
  because at least on Arndale, results were not stable enough.
* Counting is done on 'unsigned long long' instead of 'unsigned' because
  with the higher timeouts, overflows occured.

Fixes #1628
This commit is contained in:
Martin Stein 2015-07-09 16:12:00 +02:00 committed by Norman Feske
parent 3c49113e64
commit ba18ab7225
1 changed files with 27 additions and 13 deletions
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40
repos/base-hw/src/test/cpu_quota/main.cc
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@ -42,6 +42,8 @@ class Single_signal
void receive() { _sigr.wait_for_signal(); }
void submit() { _sigt.submit(); }
operator Signal_context_capability() { return _sigc; }
};
class Sync::Signal
@ -75,14 +77,14 @@ class Counter : private Thread<8 * 1024>
{
private:
char const _name;
unsigned volatile _value;
Sync::Signal _sync_sig;
unsigned volatile _stage;
Single_signal _stage_1_end;
Single_signal _stage_2_reached;
char const _name;
unsigned long long volatile _value;
Sync::Signal _sync_sig;
unsigned volatile _stage;
Single_signal _stage_1_end;
Single_signal _stage_2_reached;
inline void _stage_0_and_1(unsigned volatile & value)
inline void _stage_0_and_1(unsigned long long volatile & value)
{
_stage_1_end.receive();
_stage = 0;
@ -92,7 +94,7 @@ class Counter : private Thread<8 * 1024>
void entry()
{
unsigned volatile value = 0;
unsigned long long volatile value = 0;
while (_stage < 2) { _stage_0_and_1(value); }
_value = value;
_stage_2_reached.submit();
@ -121,33 +123,45 @@ class Counter : private Thread<8 * 1024>
void go() { _stage_1_end.submit(); }
void result() { printf("counter %c %u\n", _name, _value); }
void result() { printf("counter %c %llu\n", _name, _value); }
};
void measure(Timer::Connection & timer, Single_signal & timer_sig,
Sync::Signal & sync_sig, unsigned const sec)
{
timer.trigger_once(sec * 1000 * 1000);
sync_sig.sync();
timer_sig.receive();
}
int main()
{
enum { DURATION_BASE_SEC = 20 };
/* prepare */
Single_signal timer_sig;
Timer::Connection timer;
Sync::Connection sync;
Sync::Signal sync_sig(&sync, SYNC_SIG);
Counter counter_a('A', Cpu_session::quota_lim_upscale(10, 100), &sync);
Counter counter_b('B', Cpu_session::quota_lim_upscale(90, 100), &sync);
timer.sigh(timer_sig);
/* measure stage 1 */
sync_sig.threshold(9);
counter_a.go();
counter_b.go();
sync_sig.sync();
timer.msleep(45000);
measure(timer, timer_sig, sync_sig, 3 * DURATION_BASE_SEC);
counter_a.pause();
counter_b.destruct();
/* measure stage 2 */
sync_sig.threshold(6);
counter_a.go();
sync_sig.sync();
timer.msleep(15000);
measure(timer, timer_sig, sync_sig, DURATION_BASE_SEC);
counter_a.destruct();
/* print results */