X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;ds=sidebyside;f=ofproto%2Fofproto-dpif-governor.c;h=459f8715edb1cc1e8b433292a6d52e3e841afb9f;hb=6b4b2f598246e87237342a9179a0d29e202ebe65;hp=7e3ecfae16a33d70b46dded3cbefca03f61aad7d;hpb=e0edde6fee279cdbbf3c179f5f50adaf0c7c7f1e;p=sliver-openvswitch.git

diff --git a/ofproto/ofproto-dpif-governor.c b/ofproto/ofproto-dpif-governor.c
index 7e3ecfae1..459f8715e 100644
--- a/ofproto/ofproto-dpif-governor.c
+++ b/ofproto/ofproto-dpif-governor.c
@@ -18,7 +18,6 @@
 
 #include "ofproto-dpif-governor.h"
 
-#include <assert.h>
 #include <stdlib.h>
 
 #include "coverage.h"
@@ -54,13 +53,11 @@ enum { MAX_ELAPSED = 5000 }; /* In milliseconds. */
 
 static void governor_new_generation(struct governor *, unsigned int size);
 
-/* Creates and returns a new governor named 'name' (which is used only for log
- * messages). */
+/* Creates and returns a new governor. */
 struct governor *
-governor_create(const char *name)
+governor_create(void)
 {
     struct governor *g = xzalloc(sizeof *g);
-    g->name = xstrdup(name);
     governor_new_generation(g, MIN_SIZE);
     return g;
 }
@@ -70,7 +67,7 @@ void
 governor_destroy(struct governor *g)
 {
     if (g) {
-        VLOG_INFO("%s: disengaging", g->name);
+        VLOG_INFO("disengaging");
         free(g->table);
         free(g);
     }
@@ -93,7 +90,9 @@ governor_run(struct governor *g)
 void
 governor_wait(struct governor *g)
 {
-    poll_timer_wait_until(g->start + MAX_ELAPSED);
+    if (g->size > MIN_SIZE) {
+        poll_timer_wait_until(g->start + MAX_ELAPSED);
+    }
 }
 
 /* Returns true if 'g' has been doing only a minimal amount of work and thus
@@ -114,11 +113,11 @@ governor_is_idle(struct governor *g)
 bool
 governor_should_install_flow(struct governor *g, uint32_t hash, int n)
 {
+    int old_count, new_count;
     bool install_flow;
     uint8_t *e;
-    int count;
 
-    assert(n > 0);
+    ovs_assert(n > 0);
 
     /* Count these packets and begin a new generation if necessary. */
     g->n_packets += n;
@@ -133,19 +132,38 @@ governor_should_install_flow(struct governor *g, uint32_t hash, int n)
         governor_new_generation(g, new_size);
     }
 
+    /* If we've set up most of the flows we've seen, then we're wasting time
+     * handling most packets one at a time, so in this case instead set up most
+     * flows directly and use the remaining flows as a sample set to adjust our
+     * criteria later.
+     *
+     * The definition of "most" is conservative, but the sample size is tuned
+     * based on a few experiments with TCP_CRR mode in netperf. */
+    if (g->n_setups >= g->n_flows - g->n_flows / 16
+        && g->n_flows >= 64
+        && hash & 0x3f) {
+        g->n_shortcuts++;
+        return true;
+    }
+
     /* Do hash table processing.
      *
      * Even-numbered hash values use high-order nibbles.
      * Odd-numbered hash values use low-order nibbles. */
     e = &g->table[(hash >> 1) & (g->size - 1)];
-    count = n + (hash & 1 ? *e >> 4 : *e & 0x0f);
-    if (count >= FLOW_SETUP_THRESHOLD) {
+    old_count = (hash & 1 ? *e >> 4 : *e & 0x0f);
+    if (!old_count) {
+        g->n_flows++;
+    }
+    new_count = n + old_count;
+    if (new_count >= FLOW_SETUP_THRESHOLD) {
+        g->n_setups++;
         install_flow = true;
-        count = 0;
+        new_count = 0;
     } else {
         install_flow = false;
     }
-    *e = hash & 1 ? (count << 4) | (*e & 0x0f) : (*e & 0xf0) | count;
+    *e = hash & 1 ? (new_count << 4) | (*e & 0x0f) : (*e & 0xf0) | new_count;
 
     return install_flow;
 }
@@ -155,34 +173,39 @@ governor_should_install_flow(struct governor *g, uint32_t hash, int n)
 static void
 governor_new_generation(struct governor *g, unsigned int size)
 {
-    assert(size >= MIN_SIZE && size <= MAX_SIZE);
-    assert(is_pow2(size));
+    ovs_assert(size >= MIN_SIZE && size <= MAX_SIZE);
+    ovs_assert(is_pow2(size));
 
     /* Allocate new table, if necessary. */
     if (g->size != size) {
         if (!g->size) {
-            VLOG_INFO("%s: engaging governor with %u kB hash table",
-                      g->name, g->size / 1024);
+            VLOG_INFO("engaging governor with %u kB hash table", size / 1024);
         } else {
-            VLOG_INFO("%s: processed %u packets in %.2f s, "
-                      "%s hash table to %u kB",
-                      g->name, g->n_packets,
+            VLOG_INFO("processed %u packets in %.2f s, "
+                      "%s hash table to %u kB "
+                      "(%u hashes, %u setups, %u shortcuts)",
+                      g->n_packets,
                       (time_msec() - g->start) / 1000.0,
                       size > g->size ? "enlarging" : "shrinking",
-                      size / 1024);
+                      size / 1024,
+                      g->n_flows, g->n_setups, g->n_shortcuts);
         }
 
         free(g->table);
         g->table = xmalloc(size * sizeof *g->table);
         g->size = size;
     } else {
-        VLOG_DBG("%s: processed %u packets in %.2f s with %u kB hash table",
-                 g->name, g->n_packets, (time_msec() - g->start) / 1000.0,
-                 size / 1024);
+        VLOG_DBG("processed %u packets in %.2f s with %u kB hash table "
+                 "(%u hashes, %u setups, %u shortcuts)",
+                 g->n_packets, (time_msec() - g->start) / 1000.0,
+                 size / 1024, g->n_flows, g->n_setups, g->n_shortcuts);
     }
 
     /* Clear data for next generation. */
     memset(g->table, 0, size * sizeof *g->table);
     g->start = time_msec();
     g->n_packets = 0;
+    g->n_flows /= 2;
+    g->n_setups /= 2;
+    g->n_shortcuts = 0;
 }