procps/vmstat.c
2002-09-30 22:17:42 +00:00

278 lines
7.8 KiB
C

#define PROGNAME "vmstat"
/* Copyright 1994 by Henry Ware <al172@yfn.ysu.edu>. Copyleft same year. */
/* This attempts to display virtual memory statistics.
vmstat does not need to be run as root.
*/
/* TODO etc.
* Count the system calls. How? I don't even know where to start.
* add more items- aim at Posix 1003.2 (1003.7?) compliance, if relevant (I.
don't think it is, but let me know.)
* sometimes d(inter)<d(ticks)!! This is not possible: inter is a sum of
positive numbers including ticks. But it happens. This doesn't seem to
affect things much, however.
* It would be interesting to see when the buffers avert a block io:
Like SysV4's "sar -b"... it might fit better here, with Linux's variable
buffer size.
* Ideally, blocks in & out would be counted in 1k increments, rather than
by block: this only makes a difference for CDs and is a problematic fix.
*/
/* PROCPS
This is part of the procps package maintained by Michael K. Johnson
<johnsonm@redhat.com>; report bugs to <acahalan@cs.uml.edu>.
*/
#include "proc/sysinfo.h"
#include "proc/version.h"
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <assert.h>
#include <fcntl.h>
#include <limits.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/dir.h>
#include <dirent.h>
#define NDEBUG !DEBUG
#define BUFFSIZE 8192
#define FALSE 0
#define TRUE 1
static char buff[BUFFSIZE]; /* used in the procedures */
typedef unsigned long jiff;
/****************************************************************/
static void usage(void) {
fprintf(stderr,"usage: %s [-V] [-n] [delay [count]]\n",PROGNAME);
fprintf(stderr," -V prints version.\n");
fprintf(stderr," -n causes the headers not to be reprinted regularly.\n");
fprintf(stderr," delay is the delay between updates in seconds. \n");
fprintf(stderr," count is the number of updates.\n");
exit(EXIT_FAILURE);
}
static void crash(char *filename) {
perror(filename);
exit(EXIT_FAILURE);
}
static int winhi(void) {
struct winsize win;
int rows = 24;
if (ioctl(1, TIOCGWINSZ, &win) != -1 && win.ws_row > 0)
rows = win.ws_row;
return rows;
}
static void showheader(void){
printf("%8s%28s%8s%12s%11s%12s\n",
"procs","memory","swap","io","system","cpu");
printf("%2s %2s %2s %6s %6s %6s %6s %3s %3s %5s %5s %4s %5s %3s %3s %3s\n",
"r","b","w","swpd","free","buff","cache","si","so","bi","bo",
"in","cs","us","sy","id");
}
static void getstat(jiff *cuse, jiff *cice, jiff *csys, jiff long *cide,
unsigned *pin, unsigned *pout, unsigned *s_in, unsigned *sout,
unsigned *itot, unsigned *i1, unsigned *ct) {
static int Stat;
if ((Stat=open("/proc/stat", O_RDONLY, 0)) != -1) {
char* b;
buff[BUFFSIZE-1] = 0; /* ensure null termination in buffer */
read(Stat,buff,BUFFSIZE-1);
close(Stat);
*itot = 0;
*i1 = 1; /* ensure assert below will fail if the sscanf bombs */
b = strstr(buff, "cpu ");
sscanf(b, "cpu %lu %lu %lu %lu", cuse, cice, csys, cide);
b = strstr(buff, "page ");
sscanf(b, "page %u %u", pin, pout);
b = strstr(buff, "swap ");
sscanf(b, "swap %u %u", s_in, sout);
b = strstr(buff, "intr ");
sscanf(b, "intr %u %u", itot, i1);
b = strstr(buff, "ctxt ");
sscanf(b, "ctxt %u", ct);
}
else {
crash("/proc/stat");
}
}
static void getrunners(unsigned int *running, unsigned int *blocked,
unsigned int *swapped) {
static struct direct *ent;
static char filename[80];
static int fd;
static unsigned size;
static char c;
DIR *proc;
*running=0;
*blocked=0;
*swapped=0;
if ((proc=opendir("/proc"))==NULL) crash("/proc");
while((ent=readdir(proc))) {
if (isdigit(ent->d_name[0])) { /*just to weed out the obvious junk*/
sprintf(filename, "/proc/%s/stat", ent->d_name);
if ((fd = open(filename, O_RDONLY, 0)) != -1) { /*this weeds the rest*/
read(fd,buff,BUFFSIZE-1);
sscanf(buff, "%*d %*s %c %*d %*d %*d %*d %*d %*u %*u %*u %*u %*u %*d %*d %*d %*d %*d %*d %*u %*u %*d %*u %u %*u %*u %*u %*u %*u %*u %*u %*u %*u %*u %*u\n",&c,&size);
close(fd);
if (c=='R') {
if (size>0) (*running)++;
else (*swapped)++;
}
else if (c=='D') {
if (size>0) (*blocked)++;
else (*swapped)++;
}
}
}
}
closedir(proc);
#if 1
/* is this next line a good idea? It removes this thing which
uses (hopefully) little time, from the count of running processes */
(*running)--;
#endif
}
int main(int argc, char *argv[]) {
const char format[]="%2u %2u %2u %6u %6u %6u %6u %3u %3u %5u %5u %4u %5u %3u %3u %3u\n";
unsigned int height=22; /* window height, reset later if needed. */
#if 0
unsigned long int args[2]={0,0};
#endif
unsigned int moreheaders=TRUE;
unsigned int tog=0; /* toggle switch for cleaner code */
unsigned int i,hz;
unsigned int running,blocked,swapped;
jiff cpu_use[2], cpu_nic[2], cpu_sys[2], cpu_idl[2];
jiff duse,dsys,didl,Div,divo2;
unsigned int pgpgin[2], pgpgout[2], pswpin[2], pswpout[2];
unsigned int inter[2],ticks[2],ctxt[2];
unsigned int per=0, pero2;
unsigned long num=0;
unsigned int kb_per_page = sysconf(_SC_PAGESIZE) / 1024;
setlinebuf(stdout);
argc=0; /* redefined as number of integer arguments */
per=1;
num=0;
for (argv++;*argv;argv++) {
if ('-' ==(**argv)) {
switch (*(++(*argv))) {
case 'V':
display_version();
exit(0);
case 'n':
/* print only one header */
moreheaders=FALSE;
break;
default:
/* no other aguments defined yet. */
usage();
}
} else {
argc++;
switch (argc) {
case 1:
if ((per = atoi(*argv)) == 0)
usage();
num = ULONG_MAX;
break;
case 2:
num = atol(*argv);
break;
default:
usage();
} /* switch */
}
}
if (moreheaders) {
int tmp=winhi()-3;
height=((tmp>0)?tmp:22);
}
pero2=(per/2);
showheader();
getrunners(&running,&blocked,&swapped);
meminfo();
getstat(cpu_use,cpu_nic,cpu_sys,cpu_idl,
pgpgin,pgpgout,pswpin,pswpout,
inter,ticks,ctxt);
duse= *cpu_use + *cpu_nic;
dsys= *cpu_sys;
didl= *cpu_idl;
Div= duse+dsys+didl;
hz=sysconf(_SC_CLK_TCK); /* get ticks/s from system */
divo2= Div/2UL;
printf(format,
running,blocked,swapped,
kb_swap_used,kb_main_free,kb_main_buffers,kb_main_cached,
(*pswpin *kb_per_page*hz+divo2)/Div,
(*pswpout*kb_per_page*hz+divo2)/Div,
(*pgpgin *hz+divo2)/Div,
(*pgpgout *hz+divo2)/Div,
(*inter *hz+divo2)/Div,
(*ctxt *hz+divo2)/Div,
(100*duse+divo2)/Div,
(100*dsys+divo2)/Div,
(100*didl+divo2)/Div
);
for(i=1;i<num;i++) { /* \\\\\\\\\\\\\\\\\\\\ main loop ////////////////// */
sleep(per);
if (moreheaders && ((i%height)==0)) showheader();
tog= !tog;
getrunners(&running,&blocked,&swapped);
meminfo();
getstat(cpu_use+tog,cpu_nic+tog,cpu_sys+tog,cpu_idl+tog,
pgpgin+tog,pgpgout+tog,pswpin+tog,pswpout+tog,
inter+tog,ticks+tog,ctxt+tog);
duse= cpu_use[tog]-cpu_use[!tog] + cpu_nic[tog]-cpu_nic[!tog];
dsys= cpu_sys[tog]-cpu_sys[!tog];
didl= cpu_idl[tog]-cpu_idl[!tog];
/* idle can run backwards for a moment -- kernel "feature" */
if(cpu_idl[tog]<cpu_idl[!tog]) didl=0;
Div= duse+dsys+didl;
divo2= Div/2UL;
printf(format,
running,blocked,swapped,
kb_swap_used,kb_main_free,kb_main_buffers,kb_main_cached,
( (pswpin [tog]-pswpin [!tog])*kb_per_page+pero2 )/per,
( (pswpout[tog]-pswpout[!tog])*kb_per_page+pero2 )/per,
( pgpgin [tog]-pgpgin [!tog] +pero2 )/per,
( pgpgout[tog]-pgpgout[!tog] +pero2 )/per,
(inter[tog]-inter[!tog]+pero2)/per,
(ctxt[tog]-ctxt[!tog]+pero2)/per,
(100*duse+divo2)/Div,
(100*dsys+divo2)/Div,
(100*didl+divo2)/Div
);
}
exit(EXIT_SUCCESS);
}