From: Sebastien Godard <sysstat@orange.fr>
Date: Sun, 29 Jan 2012 13:43:53 +0000 (+0100)
Subject: [Andrey Borzenkov]: Don't take virtual devices into account in sar -b results.
X-Git-Tag: v10.0.4~5
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=7b5adcc71e0e8ef744d2910e0c0f99fe87df0726;p=sysstat

[Andrey Borzenkov]: Don't take virtual devices into account in sar -b results.

Add only physical devices stats to sar -b results. This avoids
multiplying totals when layered devices (device mapper, Linux MD,
etc) are present.

The device is assumed to be virtual if no /sys/block/<device>/device
link exists.

Only sar -b stats are modified, other statistics (e.g. sar -d) as well
as iostat continue to process virtual devices as before.

Problem noticed by Diedrich Ehlerding.
---

diff --git a/CHANGES b/CHANGES
index 001b6e2..da3891a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,8 @@
 Changes:
 
 xxxx/xx/xx: Version 10.0.4 - Sebastien Godard (sysstat <at> orange.fr)
+	* [Andrey Borzenkov]: Don't take virtual devices into account in
+	  sar -b results.
 	* configure script updated: Added --disable-stripping option.
 	  Using this option tells configure to NOT strip object files.
 	* NLS updated. Serbian translation added.
diff --git a/CREDITS b/CREDITS
index 6287931..918a943 100644
--- a/CREDITS
+++ b/CREDITS
@@ -138,6 +138,7 @@ I would also thank the following people for their hints or bug reports
 	Michael Blakeley <mike@bla[...].com>
 	Pascal Bleser <pbleser@ato[...].com>
 	Lodewijk Bonebakker <jlbonebakker@gma[...].com>
+	Andrey Borzenkov <arvidjaar@gma[...].com>
 	Jesse Brandeburg <jesse.brandeburg@int[...].com>
 	Xavier Bru <xavier.bru@bul[...].net>
 	Jason Burnett <jason@jnj[...].org>
diff --git a/common.c b/common.c
index 1bf459a..dad20c6 100644
--- a/common.c
+++ b/common.c
@@ -403,13 +403,16 @@ char *device_name(char *name)
  * ioconf.c which should be used only with kernels that don't have sysfs.
  *
  * IN:
- * @name	Device or partition name.
+ * @name		Device or partition name.
+ * @allow_virtual	TRUE if virtual devices are also accepted.
+ *			The device is assumed to be virtual if no
+ *			/sys/block/<device>/device link exists.
  *
  * RETURNS:
- * TRUE if @name is a (whole) device.
+ * TRUE if @name is not a partition.
  ***************************************************************************
  */
-int is_device(char *name)
+int is_device(char *name, int allow_virtual)
 {
 	char syspath[PATH_MAX];
 	char *slash;
@@ -418,7 +421,8 @@ int is_device(char *name)
 	while ((slash = strchr(name, '/'))) {
 		*slash = '!';
 	}
-	snprintf(syspath, sizeof(syspath), "%s/%s", SYSFS_BLOCK, name);
+	snprintf(syspath, sizeof(syspath), "%s/%s%s", SYSFS_BLOCK, name,
+		 allow_virtual ? "" : "/device");
 	
 	return !(access(syspath, F_OK));
 }
diff --git a/common.h b/common.h
index 3eff7ed..3ad5544 100644
--- a/common.h
+++ b/common.h
@@ -70,6 +70,9 @@
 
 #define NR_DISKS		4
 
+#define IGNORE_VIRTUAL_DEVICES	FALSE
+#define ACCEPT_VIRTUAL_DEVICES	TRUE
+
 /* Environment variables */
 #define ENV_TIME_FMT		"S_TIME_FORMAT"
 #define ENV_TIME_DEFTM		"S_TIME_DEF_TIME"
@@ -192,7 +195,7 @@ extern int
 extern void
 	init_nls(void);
 extern int
-	is_device(char *);
+	is_device(char *, int);
 extern double
 	ll_s_value(unsigned long long, unsigned long long, unsigned long long);
 extern double
diff --git a/iostat.c b/iostat.c
index 95d5b4d..2892afb 100644
--- a/iostat.c
+++ b/iostat.c
@@ -639,7 +639,8 @@ void read_diskstats_stat(int curr)
 
 		if (i == 14) {
 			/* Device or partition */
-			if (!dlist_idx && !DISPLAY_PARTITIONS(flags) && !is_device(dev_name))
+			if (!dlist_idx && !DISPLAY_PARTITIONS(flags) &&
+			    !is_device(dev_name, ACCEPT_VIRTUAL_DEVICES))
 				continue;
 			sdev.rd_ios     = rd_ios;
 			sdev.rd_merges  = rd_merges_or_rd_sec;
diff --git a/rd_stats.c b/rd_stats.c
index 13ad0c1..7da6b70 100644
--- a/rd_stats.c
+++ b/rd_stats.c
@@ -484,9 +484,9 @@ void read_diskstats_io(struct stats_io *st_io)
 			   &major, &minor, dev_name,
 			   &rd_ios, &rd_sec, &wr_ios, &wr_sec) == 7) {
 			
-			if (is_device(dev_name)) {
+			if (is_device(dev_name, IGNORE_VIRTUAL_DEVICES)) {
 				/*
-				 * OK: It's a device and not a partition.
+				 * OK: It's a (real) device and not a partition.
 				 * Note: Structure should have been initialized first!
 				 */
 				st_io->dk_drive      += rd_ios + wr_ios;
@@ -541,7 +541,7 @@ void read_diskstats_disk(struct stats_disk *st_disk, int nbr, int read_part)
 			if (!rd_ios && !wr_ios)
 				/* Unused device: Ignore it */
 				continue;
-			if (read_part || is_device(dev_name)) {
+			if (read_part || is_device(dev_name, ACCEPT_VIRTUAL_DEVICES)) {
 				st_disk_i = st_disk + dsk++;
 				st_disk_i->major     = major;
 				st_disk_i->minor     = minor;
@@ -2017,7 +2017,7 @@ int get_diskstats_dev_nr(int count_part, int only_used_dev)
 		if (!count_part) {
 			i = sscanf(line, "%*d %*d %s %lu %*u %*u %*u %lu",
 				   dev_name, &rd_ios, &wr_ios);
-			if ((i == 2) || !is_device(dev_name))
+			if ((i == 2) || !is_device(dev_name, ACCEPT_VIRTUAL_DEVICES))
 				/* It was a partition and not a device */
 				continue;
 			if (only_used_dev && !rd_ios && !wr_ios)