Commit 3ac1d14d authored by Wyes Karny's avatar Wyes Karny Committed by Len Brown
Browse files

tools/power turbostat: Increase the limit for fd opened 



When running turbostat, a system with 512 cpus reaches the limit for
maximum number of file descriptors that can be opened. To solve this
problem, the limit is raised to 2^15, which is a large enough number.

Below data is collected from AMD server systems while running turbostat:

|-----------+-------------------------------|
| # of cpus | # of opened fds for turbostat |
|-----------+-------------------------------|
| 128       | 260                           |
|-----------+-------------------------------|
| 192       | 388                           |
|-----------+-------------------------------|
| 512       | 1028                          |
|-----------+-------------------------------|

So, the new max limit would be sufficient up to 2^14 cpus (but this
also depends on how many counters are enabled).

Reviewed-by: default avatarDoug Smythies <dsmythies@telus.net>
Tested-by: default avatarDoug Smythies <dsmythies@telus.net>
Signed-off-by: default avatarWyes Karny <wyes.karny@amd.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent e5f4e68e

tools/power/x86/turbostat/turbostat.c

+21 −0
Original line number Diff line number Diff line
@@ -53,6 +53,8 @@ 
#define	NAME_BYTES 20

#define PATH_BYTES 128



#define MAX_NOFILE 0x8000



enum counter_scope { SCOPE_CPU, SCOPE_CORE, SCOPE_PACKAGE };

enum counter_type { COUNTER_ITEMS, COUNTER_CYCLES, COUNTER_SECONDS, COUNTER_USEC };

enum counter_format { FORMAT_RAW, FORMAT_DELTA, FORMAT_PERCENT };
@@ -6705,6 +6707,22 @@ void cmdline(int argc, char **argv) 
	}

}



void set_rlimit(void)

{

	struct rlimit limit;



	if (getrlimit(RLIMIT_NOFILE, &limit) < 0)

		err(1, "Failed to get rlimit");



	if (limit.rlim_max < MAX_NOFILE)

		limit.rlim_max = MAX_NOFILE;

	if (limit.rlim_cur < MAX_NOFILE)

		limit.rlim_cur = MAX_NOFILE;



	if (setrlimit(RLIMIT_NOFILE, &limit) < 0)

		err(1, "Failed to set rlimit");

}



int main(int argc, char **argv)

{

	int fd, ret;
@@ -6730,6 +6748,9 @@ int main(int argc, char **argv) 


	probe_sysfs();



	if (!getuid())

		set_rlimit();



	turbostat_init();



	msr_sum_record();