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 KERNEL_LINUX || 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 #if 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 KERNEL_LINUX */
  82
  83 #elif 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 #if KERNEL_LINUX
  93         /* No init needed */
  94 /* #endif KERNEL_LINUX */
  95
  96 #elif HAVE_LIBKSTAT
  97         kstat_t *ksp_chain;
  98
  99         numdisk = 0;
 100
 101         if (kc == NULL)
 102                 return;
 103
 104         for (numdisk = 0, ksp_chain = kc->kc_chain;
 105                         (numdisk < MAX_NUMDISK) && (ksp_chain != NULL);
 106                         ksp_chain = ksp_chain->ks_next)
 107         {
 108                 if (strncmp (ksp_chain->ks_class, "disk", 4)
 109                                 && strncmp (ksp_chain->ks_class, "partition", 9))
 110                         continue;
 111                 if (ksp_chain->ks_type != KSTAT_TYPE_IO)
 112                         continue;
 113                 ksp[numdisk++] = ksp_chain;
 114         }
 115 #endif /* HAVE_LIBKSTAT */
 116
 117         return;
 118 }
 119
 120 static void disk_write (char *host, char *inst, char *val)
 121 {
 122         char file[512];
 123         int status;
 124
 125         status = snprintf (file, 512, disk_filename_template, inst);
 126         if (status < 1)
 127                 return;
 128         else if (status >= 512)
 129                 return;
 130
 131         rrd_update_file (host, file, val, disk_ds_def, disk_ds_num);
 132 }
 133
 134 static void partition_write (char *host, char *inst, char *val)
 135 {
 136         char file[512];
 137         int status;
 138
 139         status = snprintf (file, 512, part_filename_template, inst);
 140         if (status < 1)
 141                 return;
 142         else if (status >= 512)
 143                 return;
 144
 145         rrd_update_file (host, file, val, part_ds_def, part_ds_num);
 146 }
 147
 148 #if DISK_HAVE_READ
 149 #define BUFSIZE 512
 150 static void disk_submit (char *disk_name,
 151                 unsigned long long read_count,
 152                 unsigned long long read_merged,
 153                 unsigned long long read_bytes,
 154                 unsigned long long read_time,
 155                 unsigned long long write_count,
 156                 unsigned long long write_merged,
 157                 unsigned long long write_bytes,
 158                 unsigned long long write_time)
 159 {
 160         char buf[BUFSIZE];
 161
 162         if (snprintf (buf, BUFSIZE, "%u:%llu:%llu:%llu:%llu:%llu:%llu:%llu:%llu",
 163                                 (unsigned int) curtime,
 164                                 read_count, read_merged, read_bytes, read_time,
 165                                 write_count, write_merged, write_bytes,
 166                                 write_time) >= BUFSIZE)
 167                 return;
 168
 169         plugin_submit (MODULE_NAME, disk_name, buf);
 170 }
 171
 172 static void partition_submit (char *part_name,
 173                 unsigned long long read_count,
 174                 unsigned long long read_bytes,
 175                 unsigned long long write_count,
 176                 unsigned long long write_bytes)
 177 {
 178         char buf[BUFSIZE];
 179
 180         if (snprintf (buf, BUFSIZE, "%u:%llu:%llu:%llu:%llu",
 181                                 (unsigned int) curtime,
 182                                 read_count, read_bytes, write_count,
 183                                 write_bytes) >= BUFSIZE)
 184                 return;
 185
 186         plugin_submit ("partition", part_name, buf);
 187 }
 188 #undef BUFSIZE
 189
 190 static void disk_read (void)
 191 {
 192 #if KERNEL_LINUX
 193         FILE *fh;
 194         char buffer[1024];
 195         char disk_name[128];
 196
 197         char *fields[32];
 198         int numfields;
 199         int fieldshift = 0;
 200
 201         int major = 0;
 202         int minor = 0;
 203
 204         unsigned int read_sectors;
 205         unsigned int write_sectors;
 206
 207         unsigned long long read_count    = 0;
 208         unsigned long long read_merged   = 0;
 209         unsigned long long read_bytes    = 0;
 210         unsigned long long read_time     = 0;
 211         unsigned long long write_count   = 0;
 212         unsigned long long write_merged  = 0;
 213         unsigned long long write_bytes   = 0;
 214         unsigned long long write_time    = 0;
 215         int is_disk = 0;
 216
 217         diskstats_t *ds, *pre_ds;
 218
 219         if ((fh = fopen ("/proc/diskstats", "r")) == NULL)
 220         {
 221                 if ((fh = fopen ("/proc/partitions", "r")) == NULL)
 222                         return;
 223
 224                 /* Kernel is 2.4.* */
 225                 fieldshift = 1;
 226         }
 227
 228         while (fgets (buffer, 1024, fh) != NULL)
 229         {
 230                 numfields = strsplit (buffer, fields, 32);
 231
 232                 if ((numfields != (14 + fieldshift)) && (numfields != 7))
 233                         continue;
 234
 235                 major = atoll (fields[0]);
 236                 minor = atoll (fields[1]);
 237
 238                 if (snprintf (disk_name, 128, "%i-%i", major, minor) < 1)
 239                         continue;
 240                 disk_name[127] = '\0';
 241
 242                 for (ds = disklist, pre_ds = disklist; ds != NULL; pre_ds = ds, ds = ds->next)
 243                         if (strcmp (disk_name, ds->name) == 0)
 244                                 break;
 245
 246                 if (ds == NULL)
 247                 {
 248                         if ((ds = (diskstats_t *) calloc (1, sizeof (diskstats_t))) == NULL)
 249                                 continue;
 250
 251                         if ((ds->name = strdup (disk_name)) == NULL)
 252                         {
 253                                 free (ds);
 254                                 continue;
 255                         }
 256
 257                         if (pre_ds == NULL)
 258                                 disklist = ds;
 259                         else
 260                                 pre_ds->next = ds;
 261                 }
 262
 263                 is_disk = 0;
 264                 if (numfields == 7)
 265                 {
 266                         /* Kernel 2.6, Partition */
 267                         read_count    = atoll (fields[3]);
 268                         read_sectors  = atoi  (fields[4]);
 269                         write_count   = atoll (fields[5]);
 270                         write_sectors = atoi  (fields[6]);
 271                 }
 272                 else if (numfields == (14 + fieldshift))
 273                 {
 274                         read_count  =  atoll (fields[3 + fieldshift]);
 275                         write_count =  atoll (fields[7 + fieldshift]);
 276
 277                         read_sectors  = atoi (fields[5 + fieldshift]);
 278                         write_sectors = atoi (fields[9 + fieldshift]);
 279
 280                         if ((fieldshift == 0) || (minor == 0))
 281                         {
 282                                 is_disk = 1;
 283                                 read_merged  = atoll (fields[4 + fieldshift]);
 284                                 read_time    = atoll (fields[6 + fieldshift]);
 285                                 write_merged = atoll (fields[8 + fieldshift]);
 286                                 write_time   = atoll (fields[10+ fieldshift]);
 287                         }
 288                 }
 289                 else
 290                 {
 291                         continue;
 292                 }
 293
 294
 295                 if (read_sectors >= ds->read_sectors)
 296                         ds->read_bytes += 512 * (read_sectors - ds->read_sectors);
 297                 else
 298                         ds->read_bytes += 512 * ((UINT_MAX - ds->read_sectors) + read_sectors);
 299
 300                 if (write_sectors >= ds->write_sectors)
 301                         ds->write_bytes += 512 * (write_sectors - ds->write_sectors);
 302                 else
 303                         ds->write_bytes += 512 * ((UINT_MAX - ds->write_sectors) + write_sectors);
 304
 305                 ds->read_sectors  = read_sectors;
 306                 ds->write_sectors = write_sectors;
 307                 read_bytes  = ds->read_bytes;
 308                 write_bytes = ds->write_bytes;
 309
 310                 /* Don't write to the RRDs if we've just started.. */
 311                 ds->poll_count++;
 312                 if (ds->poll_count <= 6)
 313                         continue;
 314
 315                 if ((read_count == 0) && (write_count == 0))
 316                         continue;
 317
 318                 if (is_disk)
 319                         disk_submit (disk_name, read_count, read_merged, read_bytes, read_time,
 320                                         write_count, write_merged, write_bytes, write_time);
 321                 else
 322                         partition_submit (disk_name, read_count, read_bytes, write_count, write_bytes);
 323         }
 324
 325         fclose (fh);
 326 /* #endif defined(KERNEL_LINUX) */
 327
 328 #elif HAVE_LIBKSTAT
 329         static kstat_io_t kio;
 330         int i;
 331
 332         if (kc == NULL)
 333                 return;
 334
 335         for (i = 0; i < numdisk; i++)
 336         {
 337                 if (kstat_read (kc, ksp[i], &kio) == -1)
 338                         continue;
 339
 340                 if (strncmp (ksp[i]->ks_class, "disk", 4) == 0)
 341                         disk_submit (ksp[i]->ks_name,
 342                                         kio.reads,  0LL, kio.nread,    kio.rtime,
 343                                         kio.writes, 0LL, kio.nwritten, kio.wtime);
 344                 else if (strncmp (ksp[i]->ks_class, "partition", 9) == 0)
 345                         partition_submit (ksp[i]->ks_name,
 346                                         kio.reads, kio.nread,
 347                                         kio.writes,kio.nwritten);
 348         }
 349 #endif /* defined(HAVE_LIBKSTAT) */
 350 } /* static void disk_read (void) */
 351 #else
 352 # define disk_read NULL
 353 #endif /* DISK_HAVE_READ */
 354
 355 void module_register (void)
 356 {
 357         plugin_register ("partition", NULL, NULL, partition_write);
 358         plugin_register (MODULE_NAME, disk_init, disk_read, disk_write);
 359 }
 360
 361 #undef MODULE_NAME