Hi rtollert,
I have created this simple program to demonstrate the allocations I see when using DAQmx (also attached as zip file).
For simplicity you can compile this directly on the target with
gcc AllocationDemo.c -L. -lnidaqmx
The output I get is this:
Malloc: 24005, Calloc: 0, Realloc: 0, Free: 24004
Notice that when you change the number of iterations from 3000 to something else, the number of Mallocs/Frees will change accordingly. I guess it would be acceptable if there were allocations in the first few loops (like a warmup time) but this is not the case here.
#include "NIDAQmx.h"
#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
#include <inttypes.h>
#define DAQmxErrChk(functionCall) if( DAQmxFailed(error=(functionCall)) ) goto Error; else
extern void *__libc_malloc(size_t size);
extern void *__libc_calloc(size_t num, size_t size);
extern void *__libc_realloc(void *ptr, size_t size);
extern void __libc_free(void *ptr);
_Atomic int64_t mallocs = 0;
_Atomic int64_t callocs = 0;
_Atomic int64_t reallocs = 0;
_Atomic int64_t frees = 0;
volatile int CountActive = 0;
void *malloc(size_t size)
{
if (size > 0 && CountActive)
{
mallocs++;
}
return __libc_malloc(size);
}
void *calloc(size_t num, size_t size)
{
if (CountActive)
{
callocs++;
}
return __libc_calloc(num, size);
}
void *realloc(void* ptr, size_t size)
{
if (CountActive)
{
reallocs++;
}
return __libc_realloc(ptr, size);
}
void free(void *ptr)
{
if (ptr)
{
if (CountActive)
{
frees++;
}
__libc_free(ptr);
}
}
int main(void)
{
int32_t error = 0;
int32_t LoopCnt = 0;
double Rate = 1000; /* 1kHz HWTSP loop */
TaskHandle _PXI1Slot5AOTask = NULL;
DAQmxErrChk(DAQmxCreateTask("PXI1Slot5AOTask", &_PXI1Slot5AOTask));
DAQmxErrChk(DAQmxCreateAOVoltageChan(_PXI1Slot5AOTask, "PXI1Slot5/ao0:3", "", -10.0, +10.0, DAQmx_Val_Volts, NULL));
DAQmxErrChk(DAQmxCfgSampClkTiming(_PXI1Slot5AOTask, NULL, Rate, DAQmx_Val_Rising, DAQmx_Val_HWTimedSinglePoint, 1))
DAQmxErrChk(DAQmxExportSignal(_PXI1Slot5AOTask,DAQmx_Val_SampleClock, "/PXI1Slot5/PXI_Trig0"));
DAQmxErrChk(DAQmxStartTask(_PXI1Slot5AOTask));
CountActive = 1; /* Start counting allocations */
double values[4] = {0.0};
int32_t writecount;
bool32 islate = 0;
while (LoopCnt < 3000 && !islate)
{
DAQmxErrChk(DAQmxWriteAnalogF64(_PXI1Slot5AOTask, 1, 1, 0, DAQmx_Val_GroupByChannel, values, &writecount, NULL));
DAQmxErrChk(DAQmxWaitForNextSampleClock(_PXI1Slot5AOTask, 4, &islate));
LoopCnt++;
}
Error:
CountActive = 0; /* Stop counting allocations */
DAQmxClearTask(_PXI1Slot5AOTask);
printf("Malloc: %" PRId64 ", Calloc: %" PRId64 ", Realloc: %" PRId64 ", Free: %" PRId64 "\n", mallocs, callocs, reallocs, frees);
return (int)error;
}
