Merge "Truncate(*1) it if WAL file is too big when opening DB" into pi-dev (0f88f865) · Commits · e / os / android_frameworks_base

core/java/android/database/sqlite/SQLiteCompatibilityWalFlags.java

+15 −0

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@ public class SQLiteCompatibilityWalFlags {
		private static volatile boolean sFlagsSet;
		private static volatile boolean sCompatibilityWalSupported;
		private static volatile String sWALSyncMode;
		private static volatile long sTruncateSize = -1;
		// This flag is used to avoid recursive initialization due to circular dependency on Settings
		private static volatile boolean sCallingGlobalSettings;

		@@ -71,6 +72,19 @@ public class SQLiteCompatibilityWalFlags {
		return sWALSyncMode;
		}

		/**
		* Override {@link com.android.internal.R.integer#db_wal_truncate_size}.
		*
		* @return the value set in the global setting, or -1 if a value is not set.
		*
		* @hide
		*/
		@VisibleForTesting
		public static long getTruncateSize() {
		initIfNeeded();
		return sTruncateSize;
		}

		private static void initIfNeeded() {
		if (sInitialized \|\| sCallingGlobalSettings) {
		return;
		@@ -115,6 +129,7 @@ public class SQLiteCompatibilityWalFlags {
		sCompatibilityWalSupported = parser.getBoolean("compatibility_wal_supported",
		SQLiteGlobal.isCompatibilityWalSupported());
		sWALSyncMode = parser.getString("wal_syncmode", SQLiteGlobal.getWALSyncMode());
		sTruncateSize = parser.getInt("truncate_size", -1);
		Log.i(TAG, "Read compatibility WAL flags: compatibility_wal_supported="
		+ sCompatibilityWalSupported + ", wal_syncmode=" + sWALSyncMode);
		sFlagsSet = true;

core/java/android/database/sqlite/SQLiteConnection.java

+36 −0

Original line number	Diff line number	Diff line
		@@ -32,6 +32,7 @@ import android.util.Printer;
		import dalvik.system.BlockGuard;
		import dalvik.system.CloseGuard;

		import java.io.File;
		import java.text.SimpleDateFormat;
		import java.util.ArrayList;
		import java.util.Date;
		@@ -303,6 +304,7 @@ public final class SQLiteConnection implements CancellationSignal.OnCancelListen
		} else {
		setSyncMode(SQLiteGlobal.getWALSyncMode());
		}
		maybeTruncateWalFile();
		} else {
		setJournalMode(mConfiguration.journalMode == null
		? SQLiteGlobal.getDefaultJournalMode() : mConfiguration.journalMode);
		@@ -312,6 +314,40 @@ public final class SQLiteConnection implements CancellationSignal.OnCancelListen
		}
		}

		/**
		* If the WAL file exists and larger than a threshold, truncate it by executing
		* PRAGMA wal_checkpoint.
		*/
		private void maybeTruncateWalFile() {
		final long threshold = SQLiteGlobal.getWALTruncateSize();
		if (DEBUG) {
		Log.d(TAG, "Truncate threshold=" + threshold);
		}
		if (threshold == 0) {
		return;
		}

		final File walFile = new File(mConfiguration.path + "-wal");
		if (!walFile.isFile()) {
		return;
		}
		final long size = walFile.length();
		if (size < threshold) {
		if (DEBUG) {
		Log.d(TAG, walFile.getAbsolutePath() + " " + size + " bytes: No need to truncate");
		}
		return;
		}

		Log.i(TAG, walFile.getAbsolutePath() + " " + size + " bytes: Bigger than "
		+ threshold + "; truncating");
		try {
		executeForString("PRAGMA wal_checkpoint(TRUNCATE)", null, null);
		} catch (SQLiteException e) {
		Log.w(TAG, "Failed to truncate the -wal file", e);
		}
		}

		private void setSyncMode(String newValue) {
		String value = executeForString("PRAGMA synchronous", null, null);
		if (!canonicalizeSyncMode(value).equalsIgnoreCase(

core/java/android/database/sqlite/SQLiteGlobal.java

+17 −0

Original line number	Diff line number	Diff line
		@@ -164,4 +164,21 @@ public final class SQLiteGlobal {
		com.android.internal.R.integer.db_default_idle_connection_timeout));
		}

		/**
		* When opening a database, if the WAL file is larger than this size, we'll truncate it.
		*
		* (If it's 0, we do not truncate.)
		*
		* @hide
		*/
		public static long getWALTruncateSize() {
		final long setting = SQLiteCompatibilityWalFlags.getTruncateSize();
		if (setting >= 0) {
		return setting;
		}
		return SystemProperties.getInt("debug.sqlite.wal.truncatesize",
		Resources.getSystem().getInteger(
		com.android.internal.R.integer.db_wal_truncate_size));
		}

		}

core/java/android/provider/Settings.java

+1 −0

Original line number	Diff line number	Diff line
		@@ -12777,6 +12777,7 @@ public final class Settings {
		* Supported keys:
		* compatibility_wal_supported (boolean)
		* wal_syncmode (String)
		* truncate_size (int)
		*
		* @hide
		*/

core/res/res/values/config.xml

+4 −0

Original line number	Diff line number	Diff line
		@@ -1873,6 +1873,10 @@
		truncate it after committing the transaction. -->
		<integer name="db_journal_size_limit">524288</integer>

		<!-- When opening a database with WAL enabled and if the wal file already exists and larger
		than this size in bytes, we'll truncate it. -->
		<integer name="db_wal_truncate_size">1048576</integer>

		<!-- The database synchronization mode when using the default journal mode.
		FULL is safest and preserves durability at the cost of extra fsyncs.
		NORMAL also preserves durability in non-WAL modes and uses checksums to ensure