/**
*
* cpulimit - a CPU limiter for Linux
*
* Copyright (C) 2005-2012, by: Angelo Marletta <angelo dot marletta at gmail dot com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
**************************************************************
*
* This is a simple program to limit the cpu usage of a process
* If you modify this code, send me a copy please
*
* Get the latest version at: http://github.com/opsengine/cpulimit
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <getopt.h>
#include <time.h>
#include <signal.h>
#include <string.h>
#include <errno.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/sysctl.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <sys/wait.h>
#if (defined __APPLE__) || (defined __FREEBSD__) || (defined __OpenBSD__)
#include <libgen.h>
#endif
#include "process_group.h"
#include "list.h"
#ifdef HAVE_SYS_SYSINFO_H
#include <sys/sysinfo.h>
#endif
#ifdef __APPLE__
#include "memrchr.c"
#endif
//some useful macro
#ifndef MIN
#define MIN(a,b) (((a)<(b))?(a):(b))
#endif
#ifndef MAX
#define MAX(a,b) (((a)>(b))?(a):(b))
#endif
//control time slot in microseconds
//each slot is splitted in a working slice and a sleeping slice
//TODO: make it adaptive, based on the actual system load
#define TIME_SLOT 100000
#define MAX_PRIORITY -10
/* GLOBAL VARIABLES */
//the "family"
struct process_group pgroup;
//pid of cpulimit
pid_t cpulimit_pid;
//name of this program (maybe cpulimit...)
char *program_name;
//number of cpu
int NCPU;
/* CONFIGURATION VARIABLES */
//verbose mode
int verbose = 0;
//lazy mode (exits if there is no process)
int lazy = 0;
//SIGINT and SIGTERM signal handler
static void quit(int sig)
{
//let all the processes continue if stopped
struct list_node *node = NULL;
if (pgroup.proclist != NULL)
{
for (node = pgroup.proclist->first; node != NULL; node = node->next) {
struct process *p = (struct process*)(node->data);
kill(p->pid, SIGCONT);
}
close_process_group(&pgroup);
}
//fix ^C little problem
printf("\r");
fflush(stdout);
exit(0);
}
//return t1-t2 in microseconds (no overflow checks, so better watch out!)
static inline unsigned long timediff(const struct timeval *t1,const struct timeval *t2)
{
return (t1->tv_sec - t2->tv_sec) * 1000000 + (t1->tv_usec - t2->tv_usec);
}
static void print_usage(FILE *stream, int exit_code)
{
fprintf(stream, "Usage: %s [OPTIONS...] TARGET\n", program_name);
fprintf(stream, " OPTIONS\n");
fprintf(stream, " -l, --limit=N percentage of cpu allowed from 0 to %d (required)\n", 100*NCPU);
fprintf(stream, " -v, --verbose show control statistics\n");
fprintf(stream, " -z, --lazy exit if there is no target process, or if it dies\n");
fprintf(stream, " -i, --include-children limit also the children processes\n");
fprintf(stream, " -h, --help display this help and exit\n");
fprintf(stream, " TARGET must be exactly one of these:\n");
fprintf(stream, " -p, --pid=N pid of the process (implies -z)\n");
fprintf(stream, " -e, --exe=FILE name of the executable program file or path name\n");
fprintf(stream, " COMMAND [ARGS] run this command and limit it (implies -z)\n");
fprintf(stream, "\nReport bugs to <marlonx80@hotmail.com>.\n");
exit(exit_code);
}
static void increase_priority() {
//find the best available nice value
int old_priority = getpriority(PRIO_PROCESS, 0);
int priority = old_priority;
while (setpriority(PRIO_PROCESS, 0, priority-1) == 0 && priority>MAX_PRIORITY) {
priority--;
}
if (priority != old_priority) {
if (verbose) printf("Priority changed to %d\n", priority);
}
else {
if (verbose) printf("Warning: Cannot change priority. Run as root or renice for best results.\n");
}
}
/* Get the number of CPUs */
static int get_ncpu() {
int ncpu;
#ifdef _SC_NPROCESSORS_ONLN
ncpu = sysconf(_SC_NPROCESSORS_ONLN);
#elif defined __APPLE__
int mib[2] = {CTL_HW, HW_NCPU};
size_t len = sizeof(ncpu);
sysctl(mib, 2, &ncpu, &len, NULL, 0);
#elif defined _GNU_SOURCE
ncpu = get_nprocs();
#else
ncpu = -1;
#endif
return ncpu;
}
int get_pid_max()
{
#ifdef __linux__
//read /proc/sys/kernel/pid_max
static char buffer[1024];
FILE *fd = fopen("/proc/sys/kernel/pid_max", "r");
if (fd==NULL) return -1;
if (fgets(buffer, sizeof(buffer), fd)==NULL) {
fclose(fd);
return -1;
}
fclose(fd);
return atoi(buffer);
#elif defined __FreeBSD__
return 99998;
#elif defined __OpenBSD__
return 99998;
#elif defined __APPLE__
return 99998;
#endif
}
void limit_process(pid_t pid, double limit, int include_children)
{
//slice of the slot in which the process is allowed to run
struct timespec twork;
//slice of the slot in which the process is stopped
struct timespec tsleep;
//when the last twork has started
struct timeval startwork;
//when the last twork has finished
struct timeval endwork;
//initialization
memset(&twork, 0, sizeof(struct timespec));
memset(&tsleep, 0, sizeof(struct timespec));
memset(&startwork, 0, sizeof(struct timeval));
memset(&endwork, 0, sizeof(struct timeval));
//last working time in microseconds
unsigned long workingtime = 0;
//generic list item
struct list_node *node;
//counter
int c = 0;
//get a better priority
increase_priority();
//build the family
init_process_group(&pgroup, pid, include_children);
if (verbose) printf("Members in the process group owned by %d: %d\n", pgroup.target_pid, pgroup.proclist->count);
//rate at which we are keeping active the processes (range 0-1)
//1 means that the process are using all the twork slice
double workingrate = -1;
while(1) {
update_process_group(&pgroup);
if (pgroup.proclist->count==0) {
if (verbose) printf("No more processes.\n");
break;
}
//total cpu actual usage (range 0-1)
//1 means that the processes are using 100% cpu
double pcpu = -1;
//estimate how much the controlled processes are using the cpu in the working interval
for (node = pgroup.proclist->first; node != NULL; node = node->next) {
struct process *proc = (struct process*)(node->data);
if (proc->cpu_usage < 0) {
continue;
}
if (pcpu < 0) pcpu = 0;
pcpu += proc->cpu_usage;
}
//adjust work and sleep time slices
if (pcpu < 0) {
//it's the 1st cycle, initialize workingrate
pcpu = limit;
workingrate = limit;
twork.tv_nsec = TIME_SLOT * limit * 1000;
}
else {
//adjust workingrate
workingrate = MIN(workingrate / pcpu * limit, 1);
twork.tv_nsec = TIME_SLOT * 1000 * workingrate;
}
tsleep.tv_nsec = TIME_SLOT * 1000 - twork.tv_nsec;
if (verbose) {
if (c%200==0)
printf("\n%%CPU\twork quantum\tsleep quantum\tactive rate\n");
if (c%10==0 && c>0)
printf("%0.2lf%%\t%6ld us\t%6ld us\t%0.2lf%%\n", pcpu*100, twork.tv_nsec/1000, tsleep.tv_nsec/1000, workingrate*100);
}
//resume processes
node = pgroup.proclist->first;
while (node != NULL)
{
struct list_node *next_node = node->next;
struct process *proc = (struct process*)(node->data);
if (kill(proc->pid,SIGCONT) != 0) {
//process is dead, remove it from family
if (verbose) fprintf(stderr, "SIGCONT failed. Process %d dead!\n", proc->pid);
//remove process from group
delete_node(pgroup.proclist, node);
remove_process(&pgroup, proc->pid);
}
node = next_node;
}
//now processes are free to run (same working slice for all)
gettimeofday(&startwork, NULL);
nanosleep(&twork, NULL);
gettimeofday(&endwork, NULL);
workingtime = timediff(&endwork, &startwork);
long delay = workingtime - twork.tv_nsec/1000;
if (c>0 && delay>10000) {
//delay is too much! signal to user?
//fprintf(stderr, "%d %ld us\n", c, delay);
}
if (tsleep.tv_nsec>0) {
//stop processes only if tsleep>0
node = pgroup.proclist->first;
while (node != NULL)
{
struct list_node *next_node = node->next;
struct process *proc = (struct process*)(node->data);
if (kill(proc->pid,SIGSTOP)!=0) {
//process is dead, remove it from family
if (verbose) fprintf(stderr, "SIGSTOP failed. Process %d dead!\n", proc->pid);
//remove process from group
delete_node(pgroup.proclist, node);
remove_process(&pgroup, proc->pid);
}
node = next_node;
}
//now the processes are sleeping
nanosleep(&tsleep,NULL);
}
c++;
}
close_process_group(&pgroup);
}
int main(int argc, char **argv) {
//argument variables
const char *exe = NULL;
int perclimit = 0;
int exe_ok = 0;
int pid_ok = 0;
int limit_ok = 0;
pid_t pid = 0;
int include_children = 0;
//get program name
char *p = (char*)memrchr(argv[0], (unsigned int)'/', strlen(argv[0]));
program_name = p==NULL ? argv[0] : (p+1);
//get current pid
cpulimit_pid = getpid();
//get cpu count
NCPU = get_ncpu();
//parse arguments
int next_option;
int option_index = 0;
//A string listing valid short options letters
const char* short_options = "+p:e:l:vzih";
//An array describing valid long options
const struct option long_options[] = {
{ "pid", required_argument, NULL, 'p' },
{ "exe", required_argument, NULL, 'e' },
{ "limit", required_argument, NULL, 'l' },
{ "verbose", no_argument, NULL, 'v' },
{ "lazy", no_argument, NULL, 'z' },
{ "include-children", no_argument, NULL, 'i' },
{ "help", no_argument, NULL, 'h' },
{ 0, 0, 0, 0 }
};
do {
next_option = getopt_long(argc, argv, short_options,long_options, &option_index);
switch(next_option) {
case 'p':
pid = atoi(optarg);
pid_ok = 1;
break;
case 'e':
exe = optarg;
exe_ok = 1;
break;
case 'l':
perclimit = atoi(optarg);
limit_ok = 1;
break;
case 'v':
verbose = 1;
break;
case 'z':
lazy = 1;
break;
case 'i':
include_children = 1;
break;
case 'h':
print_usage(stdout, 1);
break;
case '?':
print_usage(stderr, 1);
break;
case -1:
break;
default:
abort();
}
} while(next_option != -1);
if (pid_ok && (pid <= 1 || pid >= get_pid_max())) {
fprintf(stderr,"Error: Invalid value for argument PID\n");
print_usage(stderr, 1);
exit(1);
}
if (pid != 0) {
lazy = 1;
}
if (!limit_ok) {
fprintf(stderr,"Error: You must specify a cpu limit percentage\n");
print_usage(stderr, 1);
exit(1);
}
double limit = perclimit / 100.0;
if (limit<0 || limit >NCPU) {
fprintf(stderr,"Error: limit must be in the range 0-%d00\n", NCPU);
print_usage(stderr, 1);
exit(1);
}
int command_mode = optind < argc;
if (exe_ok + pid_ok + command_mode == 0) {
fprintf(stderr,"Error: You must specify one target process, either by name, pid, or command line\n");
print_usage(stderr, 1);
exit(1);
}
if (exe_ok + pid_ok + command_mode > 1) {
fprintf(stderr,"Error: You must specify exactly one target process, either by name, pid, or command line\n");
print_usage(stderr, 1);
exit(1);
}
//all arguments are ok!
signal(SIGINT, quit);
signal(SIGTERM, quit);
//print the number of available cpu
if (verbose) printf("%d cpu detected\n", NCPU);
if (command_mode) {
int i;
//executable file
const char *cmd = argv[optind];
//command line arguments
char **cmd_args = (char**)malloc((argc-optind + 1) * sizeof(char*));
if (cmd_args==NULL) exit(2);
for (i=0; i<argc-optind; i++) {
cmd_args[i] = argv[i+optind];
}
cmd_args[i] = NULL;
if (verbose) {
printf("Running command: '%s", cmd);
for (i=1; i<argc-optind; i++) {
printf(" %s", cmd_args[i]);
}
printf("'\n");
}
int child = fork();
if (child < 0) {
exit(EXIT_FAILURE);
}
else if (child == 0) {
//target process code
int ret = execvp(cmd, cmd_args);
//if we are here there was an error, show it
perror("Error");
exit(ret);
}
else {
//parent code
free(cmd_args);
int limiter = fork();
if (limiter < 0) {
exit(EXIT_FAILURE);
}
else if (limiter > 0) {
//parent
int status_process;
int status_limiter;
waitpid(child, &status_process, 0);
waitpid(limiter, &status_limiter, 0);
if (WIFEXITED(status_process)) {
if (verbose) printf("Process %d terminated with exit status %d\n", child, (int)WEXITSTATUS(status_process));
exit(WEXITSTATUS(status_process));
}
printf("Process %d terminated abnormally\n", child);
exit(status_process);
}
else {
//limiter code
if (verbose) printf("Limiting process %d\n",child);
limit_process(child, limit, include_children);
exit(0);
}
}
}
while(1) {
//look for the target process..or wait for it
pid_t ret = 0;
if (pid_ok) {
//search by pid
ret = find_process_by_pid(pid);
if (ret == 0) {
printf("No process found\n");
}
else if (ret < 0) {
printf("Process found but you aren't allowed to control it\n");
}
}
else {
//search by file or path name
ret = find_process_by_name(exe);
if (ret == 0) {
printf("No process found\n");
}
else if (ret < 0) {
printf("Process found but you aren't allowed to control it\n");
}
else {
pid = ret;
}
}
if (ret > 0) {
if (ret == cpulimit_pid) {
printf("Target process %d is cpulimit itself! Aborting because it makes no sense\n", ret);
exit(1);
}
printf("Process %d found\n", pid);
//control
limit_process(pid, limit, include_children);
}
if (lazy) break;
sleep(2);
};
exit(0);
}