Bug 615978 - Add SQLITE_DBSTATUS_* memory usage to memory reporter

Adds some finer-grained memory reporting about SQLite usage.
r=asuth

db/sqlite3/src/sqlite.def

@@ -84,6 +84,7 @@ EXPORTS
         sqlite3_data_count
         sqlite3_db_handle
         sqlite3_db_mutex
+        sqlite3_db_status
         sqlite3_declare_vtab
         sqlite3_enable_load_extension
         sqlite3_enable_shared_cache

storage/src/mozStorageConnection.cpp

@@ -48,6 +48,7 @@
 #include "nsHashSets.h"
 #include "nsAutoPtr.h"
 #include "nsIFile.h"
+#include "nsIMemoryReporter.h"
 #include "nsThreadUtils.h"
 #include "nsAutoLock.h"
 
@@ -326,6 +327,100 @@ private:
 
 } // anonymous namespace
 
+////////////////////////////////////////////////////////////////////////////////
+//// Memory Reporting
+
+class StorageMemoryReporter : public nsIMemoryReporter
+{
+public:
+  NS_DECL_ISUPPORTS
+
+  enum ReporterType {
+    LookAside_Used,
+    Cache_Used,
+    Schema_Used,
+    Stmt_Used
+  };
+
+  StorageMemoryReporter(Connection &aDBConn,
+                        ReporterType aType)
+  : mDBConn(aDBConn)
+  , mType(aType)
+  {
+  }
+
+
+  NS_IMETHOD GetPath(char **memoryPath)
+  {
+    nsCString path;
+
+    path.AppendLiteral("storage/");
+    path.Append(mDBConn.getFilename());
+
+    if (mType == LookAside_Used) {
+      path.AppendLiteral("/LookAside_Used");
+    }
+    else if (mType == Cache_Used) {
+      path.AppendLiteral("/Cache_Used");
+    }
+    else if (mType == Schema_Used) {
+      path.AppendLiteral("/Schema_Used");
+    }
+    else if (mType == Stmt_Used) {
+      path.AppendLiteral("/Stmt_Used");
+    }
+
+    *memoryPath = ::ToNewCString(path);
+    return NS_OK;
+  }
+
+  NS_IMETHOD GetDescription(char **desc)
+  {
+    if (mType == LookAside_Used) {
+      *desc = ::strdup("Number of lookaside memory slots currently checked out");
+    }
+    else if (mType == Cache_Used) {
+      *desc = ::strdup("Approximate number of bytes of heap memory used by all pager caches");
+    }
+    else if (mType == Schema_Used) {
+      *desc = ::strdup("Approximate number of bytes of heap memory used to store the schema for all databases associated with the connection");
+    }
+    else if (mType == Stmt_Used) {
+      *desc = ::strdup("Approximate number of bytes of heap and lookaside memory used by all prepared statements");
+    }
+    return NS_OK;
+  }
+
+  NS_IMETHOD GetMemoryUsed(PRInt64 *memoryUsed)
+  {
+    int type = 0;
+    if (mType == LookAside_Used) {
+      type = SQLITE_DBSTATUS_LOOKASIDE_USED;
+    }
+    else if (mType == Cache_Used) {
+      type = SQLITE_DBSTATUS_CACHE_USED;
+    }
+    else if (mType == Schema_Used) {
+      type = SQLITE_DBSTATUS_SCHEMA_USED;
+    }
+    else if (mType == Stmt_Used) {
+      type = SQLITE_DBSTATUS_STMT_USED;
+    }
+
+    int cur=0, max=0;
+    int rc = ::sqlite3_db_status(mDBConn, type, &cur, &max, 0);
+    *memoryUsed = cur;
+    return convertResultCode(rc);
+  }
+  Connection &mDBConn;
+  nsCString mFileName;
+  ReporterType mType;
+};
+NS_IMPL_THREADSAFE_ISUPPORTS1(
+  StorageMemoryReporter
+, nsIMemoryReporter
+)
+
 ////////////////////////////////////////////////////////////////////////////////
 //// Connection
 
@@ -481,6 +576,26 @@ Connection::initialize(nsIFile *aDatabaseFile,
       break;
   }
 
+  nsRefPtr<nsIMemoryReporter> reporter;
+  reporter =
+    new StorageMemoryReporter(*this, StorageMemoryReporter::LookAside_Used);
+  mMemoryReporters.AppendElement(reporter);
+
+  reporter =
+    new StorageMemoryReporter(*this, StorageMemoryReporter::Cache_Used);
+  mMemoryReporters.AppendElement(reporter);
+
+  reporter =
+    new StorageMemoryReporter(*this, StorageMemoryReporter::Schema_Used);
+  mMemoryReporters.AppendElement(reporter);
+
+  reporter = new StorageMemoryReporter(*this, StorageMemoryReporter::Stmt_Used);
+  mMemoryReporters.AppendElement(reporter);
+
+  for (PRUint32 i = 0; i < mMemoryReporters.Length(); i++) {
+    (void)::NS_RegisterMemoryReporter(mMemoryReporters[i]);
+  }
+
   return NS_OK;
 }
 
@@ -617,6 +732,10 @@ Connection::internalClose()
   }
 #endif
 
+  for (PRUint32 i = 0; i < mMemoryReporters.Length(); i++) {
+    (void)::NS_UnregisterMemoryReporter(mMemoryReporters[i]);
+  }
+
   int srv = ::sqlite3_close(mDBConn);
   NS_ASSERTION(srv == SQLITE_OK,
                "sqlite3_close failed. There are probably outstanding statements that are listed above!");

storage/src/mozStorageConnection.h

@@ -61,6 +61,7 @@ struct PRLock;
 class nsIFile;
 class nsIEventTarget;
 class nsIThread;
+class nsIMemoryReporter;
 
 namespace mozilla {
 namespace storage {
@@ -112,6 +113,7 @@ public:
 
   // fetch the native handle
   sqlite3 *GetNativeConnection() { return mDBConn; }
+  operator sqlite3 *() const { return mDBConn; }
 
   /**
    * Lazily creates and returns a background execution thread.  In the future,
@@ -201,6 +203,8 @@ private:
   sqlite3 *mDBConn;
   nsCOMPtr<nsIFile> mDatabaseFile;
 
+  nsTArray<nsCOMPtr<nsIMemoryReporter> > mMemoryReporters;
+
   /**
    * Lazily created thread for asynchronous statement execution.  Consumers
    * should use getAsyncExecutionTarget rather than directly accessing this