diff options
Diffstat (limited to 'recipes/sccd/files/scc-disk.c')
| -rw-r--r-- | recipes/sccd/files/scc-disk.c | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/recipes/sccd/files/scc-disk.c b/recipes/sccd/files/scc-disk.c new file mode 100644 index 0000000000..4fd494203a --- /dev/null +++ b/recipes/sccd/files/scc-disk.c @@ -0,0 +1,167 @@ +/* + * Copyright (c) 2006 + * Protium Computing, Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by Protium Computing, Inc. + * 4. The name of Protium Computing, Inc. may not be used to endorse or + * promote products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY PROTIUM COMPUTING ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL PROTIUM COMPUTING BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ +#include <stdio.h> +#include <fcntl.h> +#include <unistd.h> +#include <stdlib.h> +#include <string.h> +#include <strings.h> +#include <errno.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/un.h> +#include <sys/syslog.h> +#include <sys/param.h> + +struct watch_table { + char *wt_path; + int wt_status; + int wt_reads; + int wt_writes; +#define WT_INVALID 0 +#define WT_VALID 1 +#define WT_CHECK 2 +} iowt[] = { + { "/sys/block/hda/stat", WT_CHECK, 0, 0}, + { "/sys/block/hdb/stat", WT_CHECK, 0, 0}, + { "/sys/block/hdc/stat", WT_CHECK, 0, 0}, + { "/sys/block/hdd/stat", WT_CHECK, 0, 0}, + { NULL, WT_INVALID, -1, -1} +}; + +/* + * disk_activity() returns back the total number of read and writes done + * by the devices listed in the io watch table since the last call to + * disk_activity. The number of reads and writes are determined by + * opening and reading each of the valid files listed in the io watch + * table.The number of reads and writes are stored in the io watch table so + * that the next call to this routine can compare the current number of read + * and writes to those stored in the io watch table. The difference for + * each device is summed in the activity variable. The routine lazy + * evaluates the existance of the devices in the table. + * + * For the storcenter, we are only concerned with internal drives. + * + * The wt_path element must point at a diskstat file in the sysfs filesystem. + * File format can be found at: /usr/src/linux/Documentation/iostats.txt + * For this routine: + * nr, nw - number read and writes + * nmr, nmw - number of merged reads and writes + * nsr, nsw - number of the sectors read and written + * tr, tw - time spent reading and writing + * nio - raw number of ios + * tio, wtio - time spent and weighted time spent doing io + */ +int +disk_activity() +{ + int activity = 0; + char mesg[256]; + int rc, nr, nmr, nsr, tr, nw, nmw, nsw, tw, nio, tio, wtio; + FILE *f; + + struct stat st; + struct watch_table *w; + + for (w = iowt; w->wt_path; w++) { + /* + * If status ids set to check, do the lazy existence + * evaluation. If stat fails set to invalid. Don't + * worry about perms here. + */ + if ((w->wt_status == WT_CHECK) && + (stat(w->wt_path, &st) < 0)) { + sprintf(mesg, "%s not available", w->wt_path); + syslog(LOG_INFO, mesg); + w->wt_status = WT_INVALID; + } + + /* + * Short circuit the loop if invalid. + */ + if (w->wt_status == WT_INVALID) + continue; + + /* + * If it can't be opened rdonly, set to invalid + */ + if ((f = fopen(w->wt_path, "r")) < 0) { + sprintf(mesg, "Unable to open %s, no longer watching", + w->wt_path); + syslog(LOG_INFO, mesg); + w->wt_status = WT_INVALID; + continue; + } + + rc = fscanf(f, "%d %d %d %d %d %d %d %d %d %d %d", + &nr, &nmr, &nsr, &tr, + &nw, &nmw, &nsw, &tw, + &nio, &tio, &wtio); + + fclose(f); + + if (rc != 11) { + sprintf(mesg, "Unable to read %s", w->wt_path); + syslog(LOG_INFO, mesg); + continue; + } + + /* + * If we haven't seen any activity on this device before + * then just save the values and go on. This, although + * not strictly necessary, prevents the initial call to + * disk_activity returning back the base set io activity. + * Remember it takes two calls to get a true difference. + */ + if ((w->wt_reads == 0) && (w->wt_writes == 0)) { + w->wt_reads = nr; + w->wt_writes = nw; + continue; + } + + activity += (nr - w->wt_reads); + activity += (nw - w->wt_writes); + + w->wt_reads = nr; + w->wt_writes = nw; + + /* + printf("%s: %d %d %d %d %d %d %d %d %d %d %d\n", + w->wt_path, + nr, nmr, nsr, tr, + nw, nmw, nsw, tw, + nio, tio, wtio); + */ + } + + return(activity); +} |