SOLR-7463: Stop forcing MergePolicy's ''noCFSRatio'' based on the IWC ''useCompoundFile'' configuration. Use the MP's default if not specifically set

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1680663 13f79535-47bb-0310-9956-ffa450edef68

solr/CHANGES.txt

@@ -114,6 +114,15 @@ Upgrading from Solr 5.1
 * The package structure under org.apache.solr.client.solrj.io has been changed to support
   the Streaming Expression Language (SOLR-7377). Any code written with the 5.1 Streaming API will have to
   be updated to reflect these changes.
+  
+* Merge Policy's "noCFSRatio" is no longer set based on <useCompoundFile> element in the indexConfig section
+  of solrconfig.xml. This means that Solr will start using Lucene's default for MP "noCFSRatio", with this
+  new default Solr will decide if a segment should use cfs or not based on the size of the segment in relation 
+  the size of the complete index. For TieredMergePolicy for example (current default), segments will use cfs
+  if they are less than 10% of the index, otherwise cfs is disabled. Old values for this setting 
+  (1.0 for useCompoundFile=true and 0.0 for useCompoundFile=false) as well as any other value can be set 
+  inside the <mergePolicy> element in solrconfig.xml. <useCompoundFile> will only apply to newly created
+  segments. See SOLR-7463.
  
 
 Detailed Change List
@@ -409,12 +418,15 @@ Other Changes
 * SOLR-7541: Removed CollectionsHandler#createNodeIfNotExists. All calls made to this method now call
   ZkCmdExecutor#ensureExists as they were doing the same thing. Also ZkCmdExecutor#ensureExists now respects the
   CreateMode passed to it. (Varun Thacker)
-
+  
 * SOLR-6820: Make the number of version buckets used by the UpdateLog configurable as
   increasing beyond the default 256 has been shown to help with high volume indexing
   performance in SolrCloud; helps overcome a limitation where Lucene uses the request
   thread to perform expensive index housekeeping work. (Mark Miller, yonik, Timothy Potter)
 
+* SOLR-7463: Stop forcing MergePolicy's "NoCFSRatio" based on the IWC "useCompoundFile" configuration
+  (Tomás Fernández Löbbe)
+
 ==================  5.1.0 ==================
 
 Consult the LUCENE_CHANGES.txt file for additional, low level, changes in this release

solr/core/src/java/org/apache/solr/update/SolrIndexConfig.java

@@ -259,18 +259,13 @@ public class SolrIndexConfig implements MapSerializable {
       if (maxMergeDocs != -1)
         logMergePolicy.setMaxMergeDocs(maxMergeDocs);
 
-      logMergePolicy.setNoCFSRatio(getUseCompoundFile() ? 1.0 : 0.0);
-
       if (mergeFactor != -1)
         logMergePolicy.setMergeFactor(mergeFactor);
 
-
     } else if (policy instanceof TieredMergePolicy) {
       TieredMergePolicy tieredMergePolicy = (TieredMergePolicy) policy;
       fixUseCFMergePolicyInitArg(TieredMergePolicy.class);
       
-      tieredMergePolicy.setNoCFSRatio(getUseCompoundFile() ? 1.0 : 0.0);
-      
       if (mergeFactor != -1) {
         tieredMergePolicy.setMaxMergeAtOnce(mergeFactor);
         tieredMergePolicy.setSegmentsPerTier(mergeFactor);

solr/core/src/test/org/apache/solr/core/TestMergePolicyConfig.java

@@ -17,21 +17,21 @@ package org.apache.solr.core;
  * limitations under the License.
  */
 
-import org.apache.lucene.index.LeafReaderContext;
-import org.apache.solr.update.SolrIndexConfigTest;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.index.SegmentReader;
 import org.apache.lucene.index.IndexWriterConfig;
-import org.apache.lucene.index.TieredMergePolicy;
-import org.apache.lucene.index.LogMergePolicy;
+import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.index.LogByteSizeMergePolicy;
 import org.apache.lucene.index.LogDocMergePolicy;
-import org.apache.solr.util.RefCounted;
-import org.apache.solr.search.SolrIndexSearcher;
+import org.apache.lucene.index.LogMergePolicy;
+import org.apache.lucene.index.SegmentReader;
+import org.apache.lucene.index.TieredMergePolicy;
 import org.apache.solr.SolrTestCaseJ4;
+import org.apache.solr.search.SolrIndexSearcher;
+import org.apache.solr.update.SolrIndexConfigTest;
+import org.apache.solr.util.RefCounted;
 import org.junit.After;
-import java.util.concurrent.atomic.AtomicInteger;
 
 /** @see SolrIndexConfigTest */
 public class TestMergePolicyConfig extends SolrTestCaseJ4 {
@@ -42,6 +42,22 @@ public class TestMergePolicyConfig extends SolrTestCaseJ4 {
   public void after() throws Exception {
     deleteCore();
   }
+  
+  public void testSetNoCFSMergePolicyConfig() throws Exception {
+    final boolean useCompoundFile = random().nextBoolean();
+    System.setProperty("testSetNoCFSMergePolicyConfig.useCompoundFile", String.valueOf(useCompoundFile));
+    try {
+      initCore("solrconfig-mergepolicy-nocfs.xml","schema-minimal.xml");
+      IndexWriterConfig iwc = solrConfig.indexConfig.toIndexWriterConfig(h.getCore());
+      assertEquals(useCompoundFile, iwc.getUseCompoundFile());
+
+      TieredMergePolicy tieredMP = assertAndCast(TieredMergePolicy.class,
+                                                 iwc.getMergePolicy());
+      assertEquals(0.5D, tieredMP.getNoCFSRatio(), 0.0D);
+    } finally {
+      System.getProperties().remove("testSetNoCFSMergePolicyConfig.useCompoundFile");
+    }
+  }
 
   public void testDefaultMergePolicyConfig() throws Exception {
     initCore("solrconfig-mergepolicy-defaults.xml","schema-minimal.xml");
@@ -50,7 +66,7 @@ public class TestMergePolicyConfig extends SolrTestCaseJ4 {
 
     TieredMergePolicy tieredMP = assertAndCast(TieredMergePolicy.class,
                                                iwc.getMergePolicy());
-    assertEquals(0.0D, tieredMP.getNoCFSRatio(), 0.0D);
+    assertEquals(TieredMergePolicy.DEFAULT_NO_CFS_RATIO, tieredMP.getNoCFSRatio(), 0.0D);
 
     assertCommitSomeNewDocs();
     assertCompoundSegments(h.getCore(), false);
@@ -70,7 +86,6 @@ public class TestMergePolicyConfig extends SolrTestCaseJ4 {
 
     assertEquals(7, tieredMP.getMaxMergeAtOnce());
     assertEquals(7.0D, tieredMP.getSegmentsPerTier(), 0.0D);
-    assertEquals(expectCFS ? 1.0D : 0.0D, tieredMP.getNoCFSRatio(), 0.0D);
 
     assertCommitSomeNewDocs();
     assertCompoundSegments(h.getCore(), expectCFS);

solr/server/solr/configsets/data_driven_schema_configs/conf/solrconfig.xml

@@ -197,6 +197,7 @@
         <mergePolicy class="org.apache.lucene.index.TieredMergePolicy">
           <int name="maxMergeAtOnce">10</int>
           <int name="segmentsPerTier">10</int>
+          <double name="noCFSRatio">0.1</double>
         </mergePolicy>
       -->
 

solr/server/solr/configsets/sample_techproducts_configs/conf/solrconfig.xml

@@ -199,6 +199,7 @@
         <mergePolicy class="org.apache.lucene.index.TieredMergePolicy">
           <int name="maxMergeAtOnce">10</int>
           <int name="segmentsPerTier">10</int>
+          <double name="noCFSRatio">0.1</double>
         </mergePolicy>
       -->