src/disk.c

   1 /**
   2  * collectd - src/disk.c
   3  * Copyright (C) 2005,2006  Florian octo Forster
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  18  *
  19  * Authors:
  20  *   Florian octo Forster <octo at verplant.org>
  21  **/
  22
  23 #include "collectd.h"
  24 #include "common.h"
  25 #include "plugin.h"
  26
  27 #define MODULE_NAME "disk"
  28
  29 #if defined(KERNEL_LINUX) || defined(HAVE_LIBKSTAT)
  30 # define DISK_HAVE_READ 1
  31 #else
  32 # define DISK_HAVE_READ 0
  33 #endif
  34
  35 static char *disk_filename_template = "disk-%s.rrd";
  36 static char *part_filename_template = "partition-%s.rrd";
  37
  38 /* 104857600 == 100 MB */
  39 static char *disk_ds_def[] =
  40 {
  41         "DS:rcount:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  42         "DS:rmerged:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  43         "DS:rbytes:COUNTER:"COLLECTD_HEARTBEAT":0:104857600",
  44         "DS:rtime:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  45         "DS:wcount:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  46         "DS:wmerged:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  47         "DS:wbytes:COUNTER:"COLLECTD_HEARTBEAT":0:104857600",
  48         "DS:wtime:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  49         NULL
  50 };
  51 static int disk_ds_num = 8;
  52
  53 static char *part_ds_def[] =
  54 {
  55         "DS:rcount:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  56         "DS:rbytes:COUNTER:"COLLECTD_HEARTBEAT":0:104857600",
  57         "DS:wcount:COUNTER:"COLLECTD_HEARTBEAT":0:U",
  58         "DS:wbytes:COUNTER:"COLLECTD_HEARTBEAT":0:104857600",
  59         NULL
  60 };
  61 static int part_ds_num = 4;
  62
  63 #ifdef KERNEL_LINUX
  64 typedef struct diskstats
  65 {
  66         char *name;
  67
  68         /* This overflows in roughly 1361 year */
  69         unsigned int poll_count;
  70
  71         unsigned int read_sectors;
  72         unsigned int write_sectors;
  73
  74         unsigned long long read_bytes;
  75         unsigned long long write_bytes;
  76
  77         struct diskstats *next;
  78 } diskstats_t;
  79
  80 static diskstats_t *disklist;
  81 /* #endif defined(KERNEL_LINUX) */
  82
  83 #elif defined(HAVE_LIBKSTAT)
  84 #define MAX_NUMDISK 256
  85 extern kstat_ctl_t *kc;
  86 static kstat_t *ksp[MAX_NUMDISK];
  87 static int numdisk = 0;
  88 #endif /* HAVE_LIBKSTAT */
  89
  90 static void disk_init (void)
  91 {
  92 #ifdef HAVE_LIBKSTAT
  93         kstat_t *ksp_chain;
  94
  95         numdisk = 0;
  96
  97         if (kc == NULL)
  98                 return;
  99
 100         for (numdisk = 0, ksp_chain = kc->kc_chain;
 101                         (numdisk < MAX_NUMDISK) && (ksp_chain != NULL);
 102                         ksp_chain = ksp_chain->ks_next)
 103         {
 104                 if (strncmp (ksp_chain->ks_class, "disk", 4)
 105                                 && strncmp (ksp_chain->ks_class, "partition", 9))
 106                         continue;
 107                 if (ksp_chain->ks_type != KSTAT_TYPE_IO)
 108                         continue;
 109                 ksp[numdisk++] = ksp_chain;
 110         }
 111 #endif
 112
 113         return;
 114 }
 115
 116 static void disk_write (char *host, char *inst, char *val)
 117 {
 118         char file[512];
 119         int status;
 120
 121         status = snprintf (file, 512, disk_filename_template, inst);
 122         if (status < 1)
 123                 return;
 124         else if (status >= 512)
 125                 return;
 126
 127         rrd_update_file (host, file, val, disk_ds_def, disk_ds_num);
 128 }
 129
 130 static void partition_write (char *host, char *inst, char *val)
 131 {
 132         char file[512];
 133         int status;
 134
 135         status = snprintf (file, 512, part_filename_template, inst);
 136         if (status < 1)
 137                 return;
 138         else if (status >= 512)
 139                 return;
 140
 141         rrd_update_file (host, file, val, part_ds_def, part_ds_num);
 142 }
 143
 144 #if DISK_HAVE_READ
 145 #define BUFSIZE 512
 146 static void disk_submit (char *disk_name,
 147                 unsigned long long read_count,
 148                 unsigned long long read_merged,
 149                 unsigned long long read_bytes,
 150                 unsigned long long read_time,
 151                 unsigned long long write_count,
 152                 unsigned long long write_merged,
 153                 unsigned long long write_bytes,
 154                 unsigned long long write_time)
 155 {
 156         char buf[BUFSIZE];
 157
 158         if (snprintf (buf, BUFSIZE, "%u:%llu:%llu:%llu:%llu:%llu:%llu:%llu:%llu",
 159                                 (unsigned int) curtime,
 160                                 read_count, read_merged, read_bytes, read_time,
 161                                 write_count, write_merged, write_bytes,
 162                                 write_time) >= BUFSIZE)
 163                 return;
 164
 165         plugin_submit (MODULE_NAME, disk_name, buf);
 166 }
 167
 168 static void partition_submit (char *part_name,
 169                 unsigned long long read_count,
 170                 unsigned long long read_bytes,
 171                 unsigned long long write_count,
 172                 unsigned long long write_bytes)
 173 {
 174         char buf[BUFSIZE];
 175
 176         if (snprintf (buf, BUFSIZE, "%u:%llu:%llu:%llu:%llu",
 177                                 (unsigned int) curtime,
 178                                 read_count, read_bytes, write_count,
 179                                 write_bytes) >= BUFSIZE)
 180                 return;
 181
 182         plugin_submit ("partition", part_name, buf);
 183 }
 184 #undef BUFSIZE
 185
 186 static void disk_read (void)
 187 {
 188 #ifdef KERNEL_LINUX
 189         FILE *fh;
 190         char buffer[1024];
 191         char disk_name[128];
 192
 193         char *fields[32];
 194         int numfields;
 195         int fieldshift = 0;
 196
 197         int major = 0;
 198         int minor = 0;
 199
 200         unsigned int read_sectors;
 201         unsigned int write_sectors;
 202
 203         unsigned long long read_count    = 0;
 204         unsigned long long read_merged   = 0;
 205         unsigned long long read_bytes    = 0;
 206         unsigned long long read_time     = 0;
 207         unsigned long long write_count   = 0;
 208         unsigned long long write_merged  = 0;
 209         unsigned long long write_bytes   = 0;
 210         unsigned long long write_time    = 0;
 211         int is_disk = 0;
 212
 213         diskstats_t *ds, *pre_ds;
 214
 215         if ((fh = fopen ("/proc/diskstats", "r")) == NULL)
 216         {
 217                 if ((fh = fopen ("/proc/partitions", "r")) == NULL)
 218                         return;
 219
 220                 /* Kernel is 2.4.* */
 221                 fieldshift = 1;
 222         }
 223
 224         while (fgets (buffer, 1024, fh) != NULL)
 225         {
 226                 numfields = strsplit (buffer, fields, 32);
 227
 228                 if ((numfields != (14 + fieldshift)) && (numfields != 7))
 229                         continue;
 230
 231                 major = atoll (fields[0]);
 232                 minor = atoll (fields[1]);
 233
 234                 if (snprintf (disk_name, 128, "%i-%i", major, minor) < 1)
 235                         continue;
 236                 disk_name[127] = '\0';
 237
 238                 for (ds = disklist, pre_ds = disklist; ds != NULL; pre_ds = ds, ds = ds->next)
 239                         if (strcmp (disk_name, ds->name) == 0)
 240                                 break;
 241
 242                 if (ds == NULL)
 243                 {
 244                         if ((ds = (diskstats_t *) calloc (1, sizeof (diskstats_t))) == NULL)
 245                                 continue;
 246
 247                         if ((ds->name = strdup (disk_name)) == NULL)
 248                         {
 249                                 free (ds);
 250                                 continue;
 251                         }
 252
 253                         if (pre_ds == NULL)
 254                                 disklist = ds;
 255                         else
 256                                 pre_ds->next = ds;
 257                 }
 258
 259                 is_disk = 0;
 260                 if (numfields == 7)
 261                 {
 262                         /* Kernel 2.6, Partition */
 263                         read_count    = atoll (fields[3]);
 264                         read_sectors  = atoi  (fields[4]);
 265                         write_count   = atoll (fields[5]);
 266                         write_sectors = atoi  (fields[6]);
 267                 }
 268                 else if (numfields == (14 + fieldshift))
 269                 {
 270                         read_count  =  atoll (fields[3 + fieldshift]);
 271                         write_count =  atoll (fields[7 + fieldshift]);
 272
 273                         read_sectors  = atoi (fields[5 + fieldshift]);
 274                         write_sectors = atoi (fields[9 + fieldshift]);
 275
 276                         if ((fieldshift == 0) || (minor == 0))
 277                         {
 278                                 is_disk = 1;
 279                                 read_merged  = atoll (fields[4 + fieldshift]);
 280                                 read_time    = atoll (fields[6 + fieldshift]);
 281                                 write_merged = atoll (fields[8 + fieldshift]);
 282                                 write_time   = atoll (fields[10+ fieldshift]);
 283                         }
 284                 }
 285                 else
 286                 {
 287                         continue;
 288                 }
 289
 290
 291                 if (read_sectors >= ds->read_sectors)
 292                         ds->read_bytes += 512 * (read_sectors - ds->read_sectors);
 293                 else
 294                         ds->read_bytes += 512 * ((UINT_MAX - ds->read_sectors) + read_sectors);
 295
 296                 if (write_sectors >= ds->write_sectors)
 297                         ds->write_bytes += 512 * (write_sectors - ds->write_sectors);
 298                 else
 299                         ds->write_bytes += 512 * ((UINT_MAX - ds->write_sectors) + write_sectors);
 300
 301                 ds->read_sectors  = read_sectors;
 302                 ds->write_sectors = write_sectors;
 303                 read_bytes  = ds->read_bytes;
 304                 write_bytes = ds->write_bytes;
 305
 306                 /* Don't write to the RRDs if we've just started.. */
 307                 ds->poll_count++;
 308                 if (ds->poll_count <= 6)
 309                         continue;
 310
 311                 if ((read_count == 0) && (write_count == 0))
 312                         continue;
 313
 314                 if (is_disk)
 315                         disk_submit (disk_name, read_count, read_merged, read_bytes, read_time,
 316                                         write_count, write_merged, write_bytes, write_time);
 317                 else
 318                         partition_submit (disk_name, read_count, read_bytes, write_count, write_bytes);
 319         }
 320
 321         fclose (fh);
 322 /* #endif defined(KERNEL_LINUX) */
 323
 324 #elif defined(HAVE_LIBKSTAT)
 325         static kstat_io_t kio;
 326         int i;
 327
 328         if (kc == NULL)
 329                 return;
 330
 331         for (i = 0; i < numdisk; i++)
 332         {
 333                 if (kstat_read (kc, ksp[i], &kio) == -1)
 334                         continue;
 335
 336                 if (strncmp (ksp[i]->ks_class, "disk", 4) == 0)
 337                         disk_submit (ksp[i]->ks_name,
 338                                         kio.reads,  0LL, kio.nread,    kio.rtime,
 339                                         kio.writes, 0LL, kio.nwritten, kio.wtime);
 340                 else if (strncmp (ksp[i]->ks_class, "partition", 9) == 0)
 341                         partition_submit (ksp[i]->ks_name,
 342                                         kio.reads, kio.nread,
 343                                         kio.writes,kio.nwritten);
 344         }
 345 #endif /* defined(HAVE_LIBKSTAT) */
 346 } /* static void disk_read (void) */
 347 #else
 348 # define disk_read NULL
 349 #endif /* DISK_HAVE_READ */
 350
 351 void module_register (void)
 352 {
 353         plugin_register ("partition", NULL, NULL, partition_write);
 354         plugin_register (MODULE_NAME, disk_init, disk_read, disk_write);
 355 }
 356
 357 #undef MODULE_NAME