Per-rule refresh_pattern matching statistics

.. to make it blindingly obvious from the cachemgr report which rules
are completely useless. Such as when the global dot pattern (.) is
placed ahead of custom rules, or one rules pattern is always a subset
of an earlier pattern.

This also allows sysadmin to tune refresh_pattern ordering so most
commonly matching rules are first.

diff --git a/src/RefreshPattern.h b/src/RefreshPattern.h
index 506f5eefd4d8fc2c79e9657182f7db006b9cb02a..da2c5237c67e69318755de88a2baa83ef548db60 100644 (file)
--- a/src/RefreshPattern.h
+++ b/src/RefreshPattern.h
@@ -38,6 +38,13 @@ public:
 #endif
     } flags;
     int max_stale;
+
+    // statistics about how many matches this pattern has had
+    mutable struct stats_ {
+        uint64_t matchTests;
+        uint64_t matchCount;
+        // TODO: some stats to indicate how useful/less the flags are would be nice.
+    } stats;
 };
 
 #endif /* SQUID_REFRESHPATTERN_H_ */

diff --git a/src/refresh.cc b/src/refresh.cc
index f57060768a0c7143c0dc78116fbeed21e80fb969..cdd015356e14b44b46cf575ab6c609e840711622 100644 (file)
--- a/src/refresh.cc
+++ b/src/refresh.cc
@@ -107,8 +107,11 @@ refreshLimits(const char *url)
     const RefreshPattern *R;
 
     for (R = Config.Refresh; R; R = R->next) {
-        if (!regexec(&(R->compiled_pattern), url, 0, 0, 0))
+        ++(R->stats.matchTests);
+        if (!regexec(&(R->compiled_pattern), url, 0, 0, 0)) {
+            ++(R->stats.matchCount);
             return R;
+        }
     }
 
     return NULL;
@@ -694,14 +697,24 @@ refreshCountsStats(StoreEntry * sentry, struct RefreshCounts &rc)
     sum += refreshCountsStatsEntry(sentry, rc, STALE_MAX_RULE, "Stale: refresh_pattern max age rule");
     sum += refreshCountsStatsEntry(sentry, rc, STALE_LMFACTOR_RULE, "Stale: refresh_pattern last-mod factor percentage");
     sum += refreshCountsStatsEntry(sentry, rc, STALE_DEFAULT, "Stale: by default");
-
-    storeAppendPrintf(sentry, "%6d\t%6.2f\tTOTAL\n", rc.total, xpercent(rc.total, sum));
     storeAppendPrintf(sentry, "\n");
 }
 
 static void
 refreshStats(StoreEntry * sentry)
 {
+    // display per-rule counts of usage and tests
+    storeAppendPrintf(sentry, "\nRefresh pattern usage:\n\n");
+    storeAppendPrintf(sentry, "  Used      \tChecks    \t%% Matches\tPattern\n");
+    for (const RefreshPattern *R = Config.Refresh; R; R = R->next) {
+        storeAppendPrintf(sentry, "  %10" PRIu64 "\t%10" PRIu64 "\t%6.2f\t%s%s\n",
+                          R->stats.matchCount,
+                          R->stats.matchTests,
+                          xpercent(R->stats.matchCount, R->stats.matchTests),
+                          (R->flags.icase ? "-i " : ""),
+                          R->pattern);
+    }
+
     int i;
     int total = 0;