LOG=0 is now a bit faster (previously undo log entries were still written).

h2/src/main/org/h2/store/PageStore.java

@@ -835,11 +835,11 @@ public class PageStore implements CacheWriter {
     }
 
     public void writeBack(CacheObject obj) {
-        synchronized (database) {
         Page record = (Page) obj;
         if (trace.isDebugEnabled()) {
             trace.debug("writeBack " + record);
         }
+        synchronized (database) {
             record.write();
             record.setChanged(false);
         }
@@ -852,12 +852,10 @@ public class PageStore implements CacheWriter {
      * @param old the old data (if known) or null
      */
     public void logUndo(Page page, Data old) {
-        synchronized (database) {
-            if (trace.isDebugEnabled()) {
-                // if (!record.isChanged()) {
-                //     trace.debug("logUndo " + record.toString());
-                // }
+        if (logMode == LOG_MODE_OFF) {
+            return;
         }
+        synchronized (database) {
             checkOpen();
             database.checkWritingAllowed();
             if (!recoveryRunning) {
@@ -890,8 +888,10 @@ public class PageStore implements CacheWriter {
             int pos = page.getPos();
             if (SysProperties.CHECK && !recoveryRunning) {
                 // ensure the undo entry is already written
+                if (logMode != LOG_MODE_OFF) {
                     log.addUndo(pos, null);
                 }
+            }
             allocatePage(pos);
             cache.update(pos, page);
         }
@@ -976,8 +976,10 @@ public class PageStore implements CacheWriter {
     public int allocatePage() {
         int pos = allocatePage(null, 0);
         if (!recoveryRunning) {
+            if (logMode != LOG_MODE_OFF) {
                 log.addUndo(pos, emptyPage);
             }
+        }
         return pos;
     }
 
@@ -1045,8 +1047,10 @@ public class PageStore implements CacheWriter {
             cache.remove(pageId);
             if (SysProperties.CHECK && !recoveryRunning && undo) {
                 // ensure the undo entry is already written
+                if (logMode != LOG_MODE_OFF) {
                     log.addUndo(pageId, null);
                 }
+            }
             freePage(pageId);
             if (recoveryRunning) {
                 writePage(pageId, createData());