bridge: Enable system stats only if turned on in the database.

Most hypervisors have no use for this column, so populating it just wastes
CPU time.  It can still be enabled explicitly via other-config.

CC: Peter Balland <peter@nicira.com>
CC: David Tsai <dtsai@nicira.com>
Bug #5961.
NIC-397.

diff --git a/vswitchd/bridge.c b/vswitchd/bridge.c
index 17c18da..d44f480 100644 (file)
--- a/vswitchd/bridge.c
+++ b/vswitchd/bridge.c
@@ -1343,6 +1343,23 @@ iface_refresh_stats(struct iface *iface)
     ovsrec_interface_set_statistics(iface->cfg, keys, values, n);
 }
 
+static bool
+enable_system_stats(const struct ovsrec_open_vswitch *cfg)
+{
+    const char *enable;
+
+    /* Use other-config:enable-system-stats by preference. */
+    enable = get_ovsrec_key_value(&cfg->header_,
+                                  &ovsrec_open_vswitch_col_other_config,
+                                  "enable-statistics");
+    if (enable) {
+        return !strcmp(enable, "true");
+    }
+
+    /* Disable by default. */
+    return false;
+}
+
 static void
 refresh_system_stats(const struct ovsrec_open_vswitch *cfg)
 {
@@ -1350,7 +1367,9 @@ refresh_system_stats(const struct ovsrec_open_vswitch *cfg)
     struct shash stats;
 
     shash_init(&stats);
-    get_system_stats(&stats);
+    if (enable_system_stats(cfg)) {
+        get_system_stats(&stats);
+    }
 
     ovsdb_datum_from_shash(&datum, &stats);
     ovsdb_idl_txn_write(&cfg->header_, &ovsrec_open_vswitch_col_statistics,

diff --git a/vswitchd/vswitch.ovsschema b/vswitchd/vswitch.ovsschema
index e808aa3..1cec45f 100644 (file)
--- a/vswitchd/vswitch.ovsschema
+++ b/vswitchd/vswitch.ovsschema
@@ -1,6 +1,6 @@
 {"name": "Open_vSwitch",
- "version": "3.0.0",
- "cksum": "705848946 15525",
+ "version": "3.1.0",
+ "cksum": "1438894691 15636",
  "tables": {
    "Open_vSwitch": {
      "columns": {
@@ -16,6 +16,8 @@
          "type": {"key": {"type": "uuid",
                           "refTable": "SSL"},
                   "min": 0, "max": 1}},
+       "other_config": {
+         "type": {"key": "string", "value": "string", "min": 0, "max": "unlimited"}},
        "external_ids": {
          "type": {"key": "string", "value": "string",
                   "min": 0, "max": "unlimited"}},

diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml
index 2b12e29..5c532e5 100644 (file)
--- a/vswitchd/vswitch.xml
+++ b/vswitchd/vswitch.xml
@@ -25,6 +25,19 @@
         SSL used globally by the daemon.
       </column>
 
+      <column name="other_config">
+        Key-value pairs for configuring rarely used Open vSwitch features.  The
+        currently defined key-value pairs are:
+        <dl>
+          <dt><code>enable-statistics</code></dt>
+          <dd>
+            Set to <code>true</code> to enable populating the <ref
+            column="statistics"/> column or <code>false</code> (the default)
+            disable populating it.
+          </dd>
+        </dl>
+      </column>
+
       <column name="external_ids">
         Key-value pairs for use by external frameworks that integrate
         with Open vSwitch, rather than by Open vSwitch itself.  System
@@ -75,6 +88,11 @@
           apply to a platform are omitted.
         </p>
 
+        <p>
+          Statistics are disabled unless <ref column="other-config"
+          key="enable-statistics"/> is set to <code>true</code>.
+        </p>
+
         <dl>
           <dt><code>cpu</code></dt>
           <dd>