From d0573099bc5576c8dc8cde5a6a4b74146612cf33 Mon Sep 17 00:00:00 2001
From: Shalin Shekhar Mangar <shalin@apache.org>
Date: Sun, 22 Mar 2009 16:33:46 +0000
Subject: [PATCH] SOLR-1068 -- Use fsync on replicated index and configuration
 files

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@757209 13f79535-47bb-0310-9956-ffa450edef68
---
 CHANGES.txt                                   |  2 +
 .../apache/solr/common/util/FileUtils.java    | 45 ++++++++++++++++++-
 .../org/apache/solr/handler/SnapPuller.java   |  9 +++-
 3 files changed, 52 insertions(+), 4 deletions(-)

diff --git a/CHANGES.txt b/CHANGES.txt
index c65acf4a2a7..1dc582a10ce 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -365,6 +365,8 @@ Other Changes
 
 21. Upgraded to Lucene 2.9-dev r752164 (shalin)
 
+22. SOLR-1068: Use fsync on replicated index and configuration files (yonik, shalin)
+
 Build
 ----------------------
  1. SOLR-776: Added in ability to sign artifacts via Ant for releases (gsingers)
diff --git a/src/common/org/apache/solr/common/util/FileUtils.java b/src/common/org/apache/solr/common/util/FileUtils.java
index 1ecb807c833..a9bd887d4d1 100644
--- a/src/common/org/apache/solr/common/util/FileUtils.java
+++ b/src/common/org/apache/solr/common/util/FileUtils.java
@@ -19,6 +19,7 @@ package org.apache.solr.common.util;
 
 import java.io.File;
 import java.io.IOException;
+import java.io.RandomAccessFile;
 
 /**
  * @version $Id$
@@ -29,10 +30,10 @@ public class FileUtils {
    * Resolves a path relative a base directory.
    *
    * <p>
-   * This method does what "new File(base,path)" <b>Should</b> do, it wasn't 
+   * This method does what "new File(base,path)" <b>Should</b> do, it wasn't
    * completely lame: If path is absolute, then a File for that path is returned;
    * if it's not absoluve, then a File is returnd using "path" as a child 
-   * of "base") 
+   * of "base")
    * </p>
    */
   public static File resolvePath(File base, String path) throws IOException {
@@ -40,4 +41,44 @@ public class FileUtils {
     return r.isAbsolute() ? r : new File(base, path);
   }
 
+  /**
+   * Copied from Lucene's {@link org.apache.lucene.store.FSDirectory#sync(String)}
+   *
+   * @see org.apache.lucene.store.FSDirectory#sync(String)
+   *
+   * @param fullFile the File to be synced to disk
+   * @throws IOException if the file could not be synced
+   */
+  public static void sync(File fullFile) throws IOException  {
+    boolean success = false;
+    int retryCount = 0;
+    IOException exc = null;
+    while(!success && retryCount < 5) {
+      retryCount++;
+      RandomAccessFile file = null;
+      try {
+        try {
+          file = new RandomAccessFile(fullFile, "rw");
+          file.getFD().sync();
+          success = true;
+        } finally {
+          if (file != null)
+            file.close();
+        }
+      } catch (IOException ioe) {
+        if (exc == null)
+          exc = ioe;
+        try {
+          // Pause 5 msec
+          Thread.sleep(5);
+        } catch (InterruptedException ie) {
+          Thread.currentThread().interrupt();
+        }
+      }
+    }
+    if (!success)
+      // Throw original exception
+      throw exc;
+  }
+
 }
diff --git a/src/java/org/apache/solr/handler/SnapPuller.java b/src/java/org/apache/solr/handler/SnapPuller.java
index 9b57f9eb0d1..15aeca80aaa 100644
--- a/src/java/org/apache/solr/handler/SnapPuller.java
+++ b/src/java/org/apache/solr/handler/SnapPuller.java
@@ -23,6 +23,7 @@ import org.apache.solr.common.SolrException;
 import org.apache.solr.common.util.FastInputStream;
 import org.apache.solr.common.util.JavaBinCodec;
 import org.apache.solr.common.util.NamedList;
+import org.apache.solr.common.util.FileUtils;
 import org.apache.solr.core.SolrCore;
 import static org.apache.solr.handler.ReplicationHandler.*;
 import org.apache.solr.search.SolrIndexSearcher;
@@ -475,7 +476,7 @@ public class SnapPuller {
   /**
    * Copy all index files from the temp index dir to the actual index. The segments_N file is copied last.
    */
-  private boolean copyIndexFiles(File snapDir, File indexDir) {
+  private boolean copyIndexFiles(File snapDir, File indexDir) throws IOException {
     String segmentsFile = null;
     List<String> copiedfiles = new ArrayList<String>();
     for (Map<String, Object> f : filesDownloaded) {
@@ -490,11 +491,13 @@ public class SnapPuller {
         continue;
       }
       if (!copyAFile(snapDir, indexDir, fname, copiedfiles)) return false;
+      FileUtils.sync(new File(indexDir, fname));
       copiedfiles.add(fname);
     }
     //copy the segments file last
     if (segmentsFile != null) {
       if (!copyAFile(snapDir, indexDir, segmentsFile, copiedfiles)) return false;
+      FileUtils.sync(new File(indexDir, segmentsFile));
     }
     return true;
   }
@@ -516,7 +519,9 @@ public class SnapPuller {
           }
         }
         boolean status = file.renameTo(oldFile);
-        if (!status) {
+        if (status) {
+          FileUtils.sync(oldFile);
+        } else {
           throw new SolrException(SolrException.ErrorCode.SERVER_ERROR,
                   "Unable to rename: " + file + " to: " + oldFile);
         }