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#include <AK/String.h>
#include <LibCore/CElapsedTimer.h>
#include <stdio.h>
#include <unistd.h>
void usage(void)
{
printf("usage: allocate [number [unit (B/KB/MB)]]\n");
exit(1);
}
enum Unit { Bytes, KiloBytes, MegaBytes };
int main(int argc, char** argv)
{
int count = 50;
Unit unit = MegaBytes;
if (argc >= 2) {
bool ok;
count = String(argv[1]).to_uint(ok);
if (!ok) {
usage();
}
}
if (argc >= 3) {
if (strcmp(argv[2], "B") == 0)
unit = Bytes;
else if (strcmp(argv[2], "KB") == 0)
unit = KiloBytes;
else if (strcmp(argv[2], "MB") == 0)
unit = MegaBytes;
else
usage();
}
switch (unit) {
case Bytes:
break;
case KiloBytes:
count *= 1024;
break;
case MegaBytes:
count *= 1024 * 1024;
break;
}
CElapsedTimer timer;
printf("allocating memory (%d bytes)...\n", count);
timer.start();
char* ptr = (char*)malloc(count);
if (!ptr) {
printf("failed.\n");
return 1;
}
printf("done in %dms\n", timer.elapsed());
auto pages = count / 4096;
auto step = pages / 10;
CElapsedTimer timer2;
printf("writing one byte to each page of allocated memory...\n");
timer.start();
timer2.start();
for (int i = 0; i < pages; ++i) {
ptr[i * 4096] = 1;
if (i != 0 && (i % step) == 0) {
auto ms = timer2.elapsed();
if (ms == 0)
ms = 1;
auto bps = double(step * 4096) / (double(ms) / 1000);
printf("step took %dms (%fMB/s)\n", ms, bps / 1024 / 1024);
timer2.start();
}
}
printf("done in %dms\n", timer.elapsed());
printf("sleeping for ten seconds...\n");
for (int i = 0; i < 10; i++) {
printf("%d\n", i);
sleep(1);
}
printf("done.\n");
printf("freeing memory...\n");
timer.start();
free(ptr);
printf("done in %dms\n", timer.elapsed());
return 0;
}
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