online backup reliability improvement

andreitokar · Jul 4, 2024 · 0bd1376 · 0bd1376
1 parent 575302d
commit 0bd1376
Show file tree

Hide file tree

Showing 4 changed files with 43 additions and 24 deletions.
diff --git a/h2/src/main/org/h2/mvstore/FileStore.java b/h2/src/main/org/h2/mvstore/FileStore.java
@@ -31,6 +31,7 @@
 import java.util.Set;
 import java.util.TreeMap;
 import java.util.concurrent.ArrayBlockingQueue;
+import java.util.concurrent.Callable;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentLinkedDeque;
 import java.util.concurrent.ConcurrentMap;
@@ -85,7 +86,7 @@ public abstract class FileStore<C extends Chunk<C>>
     private static final int FORMAT_READ_MIN = 3;
     private static final int FORMAT_READ_MAX = 3;
 
-    MVStore mvStore;
+    private MVStore mvStore;
     private boolean closed;
 
     /**
@@ -1357,7 +1358,8 @@ public boolean isSpaceReused() {
         return true;
     }
 
-    public void setReuseSpace(boolean reuseSpace) {
+    public boolean setReuseSpace(boolean reuseSpace) {
+        return isSpaceReused();
     }
 
     protected final void store() {
@@ -1876,7 +1878,7 @@ private static <C extends Chunk<C>> HashSet<Integer> createIdSet(Iterable<C> toC
         return set;
     }
 
-    public void executeFileStoreOperation(Runnable operation) {
+    public <T> T executeFileStoreOperation(Callable<T> operation) {
         // because serializationExecutor is a single-threaded one and
         // all task submissions to it are done under storeLock,
         // it is guaranteed, that upon this dummy task completion
@@ -1888,7 +1890,9 @@ public void executeFileStoreOperation(Runnable operation) {
             // are done under serializationLock, and upon this dummy task completion
             // it will be no pending / in-progress task here
             Utils.flushExecutor(bufferSaveExecutor);
-            operation.run();
+            return operation.call();
+        } catch (Exception ex) {
+            throw new RuntimeException(ex);
         } finally {
             serializationLock.unlock();
         }

diff --git a/h2/src/main/org/h2/mvstore/MVStore.java b/h2/src/main/org/h2/mvstore/MVStore.java
@@ -915,11 +915,13 @@ public boolean hasUnsavedChanges() {
         return fileStore != null && fileStore.hasChangesSince(lastStoredVersion);
     }
 
-    public void executeFilestoreOperation(Runnable operation) {
+    public <T> T executeFilestoreOperation(Callable<T> operation) {
+        T result = null;
         storeLock.lock();
         try {
             checkNotClosed();
-            fileStore.executeFileStoreOperation(operation);
+            result = fileStore.executeFileStoreOperation(operation);
+            return result;
         } catch (MVStoreException e) {
             panic(e);
         } catch (Throwable e) {
@@ -928,6 +930,7 @@ public void executeFilestoreOperation(Runnable operation) {
         } finally {
             unlockAndCheckPanicCondition();
         }
+        return result;
     }
 
     <R> R tryExecuteUnderStoreLock(Callable<R> operation) throws InterruptedException {
@@ -1107,9 +1110,10 @@ public boolean isSpaceReused() {
      * than the write operations).
      *
      * @param reuseSpace the new value
+     * @return previous state of the flag
      */
-    public void setReuseSpace(boolean reuseSpace) {
-        fileStore.setReuseSpace(reuseSpace);
+    public boolean setReuseSpace(boolean reuseSpace) {
+        return executeFilestoreOperation(() -> fileStore.setReuseSpace(reuseSpace));
     }
 
     public int getRetentionTime() {

diff --git a/h2/src/main/org/h2/mvstore/RandomAccessStore.java b/h2/src/main/org/h2/mvstore/RandomAccessStore.java
@@ -116,8 +116,10 @@ public boolean isSpaceReused() {
     }
 
     @Override
-    public void setReuseSpace(boolean reuseSpace) {
+    public boolean setReuseSpace(boolean reuseSpace) {
+        boolean current = this.reuseSpace;
         this.reuseSpace = reuseSpace;
+        return current;
     }
 
     @Override
@@ -470,15 +472,18 @@ public void compactMoveChunks(int targetFillRate, long moveSize, MVStore mvStore
                 } finally {
                     saveChunkLock.unlock();
                 }
+                return null;
             });
         }
     }
 
     private void compactMoveChunks(long moveSize) {
-        long start = getFirstFree() / FileStore.BLOCK_SIZE;
-        Iterable<SFChunk> chunksToMove = findChunksToMove(start, moveSize);
-        if (chunksToMove != null) {
-            compactMoveChunks(chunksToMove);
+        if (isSpaceReused()) {
+            long start = getFirstFree() / FileStore.BLOCK_SIZE;
+            Iterable<SFChunk> chunksToMove = findChunksToMove(start, moveSize);
+            if (chunksToMove != null) {
+                compactMoveChunks(chunksToMove);
+            }
         }
     }
 

diff --git a/h2/src/main/org/h2/mvstore/SingleFileStore.java b/h2/src/main/org/h2/mvstore/SingleFileStore.java
@@ -231,20 +231,26 @@ protected long getAfterLastBlock_() {
 
     @Override
     public void backup(ZipOutputStream out) throws IOException {
-        boolean before = isSpaceReused();
-        setReuseSpace(false);
+        String f = correctFileName(FilePath.get(getFileName()).toRealPath().getName());
+        out.putNextEntry(new ZipEntry(f));
+        FileChannel in = originalFileChannel != null ? originalFileChannel : fileChannel;
+        MVStore mvStore = getMvStore();
+        boolean before = mvStore.setReuseSpace(false);
         try {
-            backupFile(out, getFileName(), originalFileChannel != null ? originalFileChannel : fileChannel);
+
+            IOUtils.copy(in, out);
+
+            mvStore.executeFilestoreOperation(() -> {
+                try {
+                    IOUtils.copy(in, out);
+                } catch (IOException ex) {
+                    throw new RuntimeException(ex);
+                }
+                return null;
+            });
         } finally {
-            setReuseSpace(before);
+            mvStore.setReuseSpace(before);
         }
-    }
-
-    private static void backupFile(ZipOutputStream out, String fileName, FileChannel in) throws IOException {
-        String f = FilePath.get(fileName).toRealPath().getName();
-        f = correctFileName(f);
-        out.putNextEntry(new ZipEntry(f));
-        IOUtils.copy(in, out);
         out.closeEntry();
     }