Measurement data collection stops short of needed amount.

[huburb4n]

When the collected parameters count exceeds a certain size, powertop stops collecting data.

The compile time constants below, defined in parameters.h

#define MAX_KEEP 700
#define MAX_PARAM 750

are used in persistent.ccp in
void load_results(const char *filename)
to limit the amount of results loaded into "past_results"

			overflow_index = 50 + (rand() % MAX_KEEP);
			if (past_results.size() >= MAX_PARAM) {
			/* memory leak, must free old one first */
				past_results[overflow_index] = bundle;
			} else {
				past_results.push_back(bundle);
			}

However, in parameters.cpp in
int global_power_valid(void)
there is a condition which dynamically defines the desired number of measurements as a function of parameters size:

	if (past_results.size() > 3 * all_parameters.parameters.size())
		return 1;

without any consideration for the relation between MAX_PARAM and the calculated value.

Potential fixes:

• accept MAX_PARAM measurements regardless of the parameter count

	if (past_results.size() > min(3 * all_parameters.parameters.size(), MAX_PARAM-1))
		return 1;

• or increase the storage limits to

#define MAX_KEEP 974
#define MAX_PARAM 1024

This last approach allows powertop to finish its data collection and continue normally on my test platform where
the number of measurements needed is displayed as 907.

• or any other approach which takes into account the relationship illustrated above.