Fix SNMP cacheNumObjCount -- number of cached objects

CONTRIBUTORS

@@ -88,6 +88,7 @@ Thank you!
     Brian Degenhardt <bmd@mp3.com>
     Brian Denehy <B-Denehy@adfa.oz.au>
     Bruce Murphy <pack-squid@rattus.net>
+    Carl Vuosalo <cvuosalo@cern.ch>
     Carson Gaspar <carson@cs.columbia.edu>
     Carson Gaspar <carson@lehman.com>
     Carsten Grzemba <cgrzemba@opencsw.org>

src/MemStore.cc

@@ -207,6 +207,14 @@ MemStore::getStats(StoreInfoStats &stats) const
     const size_t pageSize = Ipc::Mem::PageSize();
 
     stats.mem.shared = true;
+
+    // In SMP mode, only the first worker reports shared memory stats to avoid
+    // adding up same-cache positive stats (reported by multiple worker
+    // processes) when Coordinator aggregates worker-reported stats.
+    // See also: Store::Disk::doReportStat().
+    if (UsingSmp() && KidIdentifier != 1)
+        return;
+
     stats.mem.capacity =
         Ipc::Mem::PageLimit(Ipc::Mem::PageId::cachePage) * pageSize;
     stats.mem.size =

src/StoreStats.cc

@@ -23,22 +23,10 @@ StoreInfoStats::operator +=(const StoreInfoStats &stats)
     // Assume that either all workers use shared memory cache or none do.
     // It is possible but difficult to report correct stats for an arbitrary
     // mix, and only rather unusual deployments can benefit from mixing.
-
-    // If workers share memory, we will get shared stats from those workers
-    // and non-shared stats from other processes. Ignore order and also
-    // ignore other processes stats because they are zero in most setups.
-    if (stats.mem.shared) { // workers share memory
-        // use the latest reported stats, they all should be about the same
-        mem.shared = true;
-        mem.size = stats.mem.size;
-        mem.capacity = stats.mem.capacity;
-        mem.count = stats.mem.count;
-    } else if (!mem.shared) { // do not corrupt shared stats, if any
-        // workers do not share so we must add everything up
-        mem.size += stats.mem.size;
-        mem.capacity += stats.mem.capacity;
-        mem.count += stats.mem.count;
-    }
+    mem.shared = mem.shared || stats.mem.shared; // TODO: Remove mem.shared as effectively unused?
+    mem.size += stats.mem.size;
+    mem.capacity += stats.mem.capacity;
+    mem.count += stats.mem.count;
 
     store_entry_count += stats.store_entry_count;
     mem_object_count += stats.mem_object_count;

src/snmp_agent.cc

@@ -25,6 +25,8 @@
 #include "StatCounters.h"
 #include "StatHist.h"
 #include "Store.h"
+#include "store/Controller.h"
+#include "StoreStats.h"
 #include "tools.h"
 #include "util.h"
 
@@ -409,11 +411,14 @@ snmp_prfSysFn(variable_list * Var, snint * ErrP)
                                       SMI_GAUGE32);
         break;
 
-    case PERF_SYS_NUMOBJCNT:
+    case PERF_SYS_NUMOBJCNT: {
+        StoreInfoStats stats;
+        Store::Root().getStats(stats);
         Answer = snmp_var_new_integer(Var->name, Var->name_length,
-                                      (snint) StoreEntry::inUseCount(),
+                                      (snint) (stats.mem.count + stats.swap.count),
                                       SMI_GAUGE32);
         break;
+    }
 
     default:
         *ErrP = SNMP_ERR_NOSUCHNAME;