1 /* vmstat.c - Report virtual memory statistics. 2 * 3 * Copyright 2012 Elie De Brauwer <eliedebrauwer (at) gmail.com> 4 * 5 * TODO: I have no idea how "system" category is calculated. 6 * whatever we're doing isn't matching what other implementations are doing. 7 8 USE_VMSTAT(NEWTOY(vmstat, ">2n", TOYFLAG_BIN)) 9 10 config VMSTAT 11 bool "vmstat" 12 default y 13 help 14 usage: vmstat [-n] [DELAY [COUNT]] 15 16 Print virtual memory statistics, repeating each DELAY seconds, COUNT times. 17 (With no DELAY, prints one line. With no COUNT, repeats until killed.) 18 19 Show processes running and blocked, kilobytes swapped, free, buffered, and 20 cached, kilobytes swapped in and out per second, file disk blocks input and 21 output per second, interrupts and context switches per second, percent 22 of CPU time spent running user code, system code, idle, and awaiting I/O. 23 First line is since system started, later lines are since last line. 24 25 -n Display the header only once 26 */ 27 28 #define FOR_vmstat 29 #include "toys.h" 30 31 struct vmstat_proc { 32 // From /proc/stat (jiffies) 33 uint64_t user, nice, sys, idle, wait, irq, sirq, intr, ctxt, running, blocked; 34 // From /proc/meminfo (units are kb) 35 uint64_t memfree, buffers, cached, swapfree, swaptotal; 36 // From /proc/vmstat (units are kb) 37 uint64_t io_in, io_out; 38 // From /proc/vmstat (units are pages) 39 uint64_t swap_in, swap_out; 40 }; 41 42 // All the elements of vmstat_proc are the same size, so we can populate it as 43 // a big array, then read the elements back out by name 44 static void get_vmstat_proc(struct vmstat_proc *vmstat_proc) 45 { 46 char *vmstuff[] = { "/proc/stat", "cpu ", 0, 0, 0, 0, 0, 0, 47 "intr ", "ctxt ", "procs_running ", "procs_blocked ", "/proc/meminfo", 48 "MemFree: ", "Buffers: ", "Cached: ", "SwapFree: ", "SwapTotal: ", 49 "/proc/vmstat", "pgpgin ", "pgpgout ", "pswpin ", "pswpout " }; 50 uint64_t *new = (uint64_t *)vmstat_proc; 51 char *p = p, *name = name; 52 int i, j; 53 54 // We use vmstuff to fill out vmstat_proc as an array of uint64_t: 55 // Strings starting with / are the file to find next entries in 56 // Any other string is a key to search for, with decimal value right after 57 // 0 means parse another value on same line as last key 58 59 for (i = 0; i<sizeof(vmstuff)/sizeof(char *); i++) { 60 if (!vmstuff[i]) p++; 61 else if (*vmstuff[i] == '/') { 62 xreadfile(name = vmstuff[i], toybuf, sizeof(toybuf)); 63 64 continue; 65 } else if (!(p = strafter(toybuf, vmstuff[i]))) goto error; 66 if (1 != sscanf(p, "%"PRIu64"%n", new++, &j)) goto error; 67 p += j; 68 } 69 70 return; 71 72 error: 73 error_exit("No %sin %s\n", vmstuff[i], name); 74 } 75 76 void vmstat_main(void) 77 { 78 struct vmstat_proc top[2]; 79 int i, loop_delay = 0, loop_max = 0; 80 unsigned loop, rows = (toys.optflags & FLAG_n) ? 0 : 25, 81 page_kb = sysconf(_SC_PAGESIZE)/1024; 82 char *headers="r\0b\0swpd\0free\0buff\0cache\0si\0so\0bi\0bo\0in\0cs\0us\0" 83 "sy\0id\0wa", lengths[] = {2,2,6,6,6,6,4,4,5,5,4,4,2,2,2,2}; 84 85 memset(top, 0, sizeof(top)); 86 if (toys.optc) loop_delay = atolx_range(toys.optargs[0], 0, INT_MAX); 87 if (toys.optc > 1) loop_max = atolx_range(toys.optargs[1], 1, INT_MAX) - 1; 88 89 for (loop = 0; !loop_max || loop <= loop_max; loop++) { 90 unsigned idx = loop&1, offset = 0, expected = 0; 91 uint64_t units, total_hz, *ptr = (uint64_t *)(top+idx), 92 *oldptr = (uint64_t *)(top+!idx); 93 94 if (loop && loop_delay) sleep(loop_delay); 95 96 // Print headers 97 if (rows>3 && !(loop % (rows-3))) { 98 char *header = headers; 99 100 if (isatty(1)) terminal_size(0, &rows); 101 else rows = 0; 102 103 printf("procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----\n"); 104 for (i=0; i<sizeof(lengths); i++) { 105 printf(" %*s"+!i, lengths[i], header); 106 header += strlen(header)+1; 107 } 108 xputc('\n'); 109 } 110 111 // Read data and combine some fields we display as aggregates 112 get_vmstat_proc(top+idx); 113 top[idx].running--; // Don't include ourselves 114 top[idx].user += top[idx].nice; 115 top[idx].sys += top[idx].irq + top[idx].sirq; 116 top[idx].swaptotal -= top[idx].swapfree; 117 118 // Collect unit adjustments (outside the inner loop to save time) 119 120 if (!loop) { 121 char *s = toybuf; 122 123 xreadfile("/proc/uptime", toybuf, sizeof(toybuf)); 124 while (*(s++) > ' '); 125 sscanf(s, "%"PRIu64, &units); 126 } else units = loop_delay; 127 128 // add up user, sys, idle, and wait time used since last time 129 // (Already appended nice to user) 130 total_hz = 0; 131 for (i=0; i<4; i++) total_hz += ptr[i+!!i] - oldptr[i+!!i]; 132 133 // Output values in order[]: running, blocked, swaptotal, memfree, buffers, 134 // cache, swap_in, swap_out, io_in, io_out, sirq, ctxt, user, sys, idle,wait 135 136 for (i=0; i<sizeof(lengths); i++) { 137 char order[] = {9, 10, 15, 11, 12, 13, 18, 19, 16, 17, 6, 8, 0, 2, 3, 4}; 138 uint64_t out = ptr[order[i]]; 139 int len; 140 141 // Adjust rate and units 142 if (i>5) out -= oldptr[order[i]]; 143 if (order[i]<7) out = ((out*100) + (total_hz/2)) / total_hz; 144 else if (order[i]>17) out = ((out * page_kb)+(units-1))/units; 145 else if (order[i]>15) out = ((out)+(units-1))/units; 146 else if (order[i]<9) out = (out+(units-1)) / units; 147 148 // If a field was too big to fit in its slot, try to compensate later 149 expected += lengths[i] + !!i; 150 len = expected - offset - !!i; 151 if (len < 0) len = 0; 152 offset += printf(" %*"PRIu64+!i, len, out); 153 } 154 xputc('\n'); 155 156 if (!loop_delay) break; 157 } 158 } 159
