Revert "YARN-9873. Mutation API Config Change updates Version Number. Contributed by Prabhu Joseph"

This reverts commit 3a0afcfb7f196bee8e534a3e80211bfa077b2aee.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/MutableConfigurationProvider.java

@@ -65,12 +65,6 @@ public interface MutableConfigurationProvider {
    */
   Configuration getConfiguration();
 
-  /**
-   * Get the last updated scheduler config version.
-   * @return Last updated scheduler config version.
-   */
-  long getConfigVersion() throws Exception;
-
   void formatConfigurationInStore(Configuration conf) throws Exception;
 
   /**

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/FSSchedulerConfigurationStore.java

@@ -148,13 +148,6 @@ public class FSSchedulerConfigurationStore extends YarnConfigurationStore {
     tempConfigPath = null;
   }
 
-  @Override
-  public long getConfigVersion() throws Exception {
-    String version = getLatestConfigPath().getName().
-        substring(YarnConfiguration.CS_CONFIGURATION_FILE.length() + 1);
-    return Long.parseLong(version);
-  }
-
   private void finalizeFileSystemFile() throws IOException {
     // call confirmMutation() make sure tempConfigPath is not null
     Path finalConfigPath = getFinalConfigPath(tempConfigPath);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/InMemoryConfigurationStore.java

@@ -33,13 +33,11 @@ public class InMemoryConfigurationStore extends YarnConfigurationStore {
 
   private Configuration schedConf;
   private LogMutation pendingMutation;
-  private long configVersion;
 
   @Override
   public void initialize(Configuration conf, Configuration schedConf,
       RMContext rmContext) {
     this.schedConf = schedConf;
-    this.configVersion = System.currentTimeMillis();
   }
 
   @Override
@@ -59,7 +57,6 @@ public class InMemoryConfigurationStore extends YarnConfigurationStore {
         }
       }
     }
-    this.configVersion = System.currentTimeMillis();
     pendingMutation = null;
   }
 
@@ -73,11 +70,6 @@ public class InMemoryConfigurationStore extends YarnConfigurationStore {
     return schedConf;
   }
 
-  @Override
-  public long getConfigVersion() throws Exception {
-    return configVersion;
-  }
-
   @Override
   public List<LogMutation> getConfirmedConfHistory(long fromId) {
     // Unimplemented.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/LeveldbConfigurationStore.java

@@ -68,7 +68,6 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
   private static final String DB_NAME = "yarn-conf-store";
   private static final String LOG_KEY = "log";
   private static final String VERSION_KEY = "version";
-  private static final String CONF_VERSION_KEY = "conf-version";
 
   private DB db;
   private long maxLogs;
@@ -125,10 +124,6 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
           return 1;
         } else if (key2Str.equals(LOG_KEY)) {
           return -1;
-        } else if (key1Str.equals(CONF_VERSION_KEY)) {
-          return 1;
-        } else if (key2Str.equals(CONF_VERSION_KEY)) {
-          return -1;
         }
         return key1Str.compareTo(key2Str);
       }
@@ -151,10 +146,6 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
     File dbfile = new File(storeRoot.toString());
     try {
       db = JniDBFactory.factory.open(dbfile, options);
-      if (db.get(bytes(CONF_VERSION_KEY)) == null) {
-        db.put(bytes(CONF_VERSION_KEY),
-            bytes(String.valueOf(System.currentTimeMillis())));
-      }
     } catch (NativeDB.DBException e) {
       if (e.isNotFound() || e.getMessage().contains(" does not exist ")) {
         LOG.info("Creating conf database at " + dbfile);
@@ -167,8 +158,6 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
             initBatch.put(bytes(kv.getKey()), bytes(kv.getValue()));
           }
           db.write(initBatch);
-          db.put(bytes(CONF_VERSION_KEY),
-              bytes(String.valueOf(System.currentTimeMillis())));
         } catch (DBException dbErr) {
           throw new IOException(dbErr.getMessage(), dbErr);
         }
@@ -226,8 +215,6 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
       }
     }
     db.write(updateBatch);
-    db.put(bytes(CONF_VERSION_KEY),
-        bytes(String.valueOf(System.currentTimeMillis())));
     pendingMutation = null;
   }
 
@@ -263,8 +250,7 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
       Map.Entry<byte[], byte[]> entry = itr.next();
       String key = new String(entry.getKey(), StandardCharsets.UTF_8);
       String value = new String(entry.getValue(), StandardCharsets.UTF_8);
-      if (key.equals(LOG_KEY) || key.equals(VERSION_KEY) ||
-          key.equals(CONF_VERSION_KEY)) {
+      if (key.equals(LOG_KEY) || key.equals(VERSION_KEY)) {
         break;
       }
       config.set(key, value);
@@ -272,13 +258,6 @@ public class LeveldbConfigurationStore extends YarnConfigurationStore {
     return config;
   }
 
-  @Override
-  public long getConfigVersion() throws Exception {
-    String version = new String(db.get(bytes(CONF_VERSION_KEY)),
-        StandardCharsets.UTF_8);
-    return Long.parseLong(version);
-  }
-
   @Override
   public List<LogMutation> getConfirmedConfHistory(long fromId) {
     return null; // unimplemented

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/MutableCSConfigurationProvider.java

@@ -134,11 +134,6 @@ public class MutableCSConfigurationProvider implements CSConfigurationProvider,
     return new Configuration(schedConf);
   }
 
-  @Override
-  public long getConfigVersion() throws Exception {
-    return confStore.getConfigVersion();
-  }
-
   @Override
   public ConfigurationMutationACLPolicy getAclMutationPolicy() {
     return aclMutationPolicy;

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/YarnConfigurationStore.java

@@ -132,12 +132,6 @@ public abstract class YarnConfigurationStore {
    */
   public abstract void format() throws Exception;
 
-  /**
-   * Get the last updated config version.
-   * @return Last updated config version.
-   */
-  public abstract long getConfigVersion() throws Exception;
-
   /**
    * Get a list of confirmed configuration mutations starting from a given id.
    * @param fromId id from which to start getting mutations, inclusive

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/ZKConfigurationStore.java

@@ -62,13 +62,11 @@ public class ZKConfigurationStore extends YarnConfigurationStore {
   private static final String LOGS_PATH = "LOGS";
   private static final String CONF_STORE_PATH = "CONF_STORE";
   private static final String FENCING_PATH = "FENCING";
-  private static final String CONF_VERSION_PATH = "CONF_VERSION";
 
   private String zkVersionPath;
   private String logsPath;
   private String confStorePath;
   private String fencingNodePath;
-  private String confVersionPath;
 
   @VisibleForTesting
   protected ZKCuratorManager zkManager;
@@ -91,7 +89,6 @@ public class ZKConfigurationStore extends YarnConfigurationStore {
     this.logsPath = getNodePath(znodeParentPath, LOGS_PATH);
     this.confStorePath = getNodePath(znodeParentPath, CONF_STORE_PATH);
     this.fencingNodePath = getNodePath(znodeParentPath, FENCING_PATH);
-    this.confVersionPath = getNodePath(znodeParentPath, CONF_VERSION_PATH);
 
     zkManager.createRootDirRecursively(znodeParentPath, zkAcl);
     zkManager.delete(fencingNodePath);
@@ -102,12 +99,6 @@ public class ZKConfigurationStore extends YarnConfigurationStore {
           serializeObject(new LinkedList<LogMutation>()), -1);
     }
 
-    if (!zkManager.exists(confVersionPath)) {
-      zkManager.create(confVersionPath);
-      zkManager.setData(confVersionPath,
-          String.valueOf(System.currentTimeMillis()), -1);
-    }
-
     if (!zkManager.exists(confStorePath)) {
       zkManager.create(confStorePath);
       HashMap<String, String> mapSchedConf = new HashMap<>();
@@ -115,8 +106,6 @@ public class ZKConfigurationStore extends YarnConfigurationStore {
         mapSchedConf.put(entry.getKey(), entry.getValue());
       }
       zkManager.setData(confStorePath, serializeObject(mapSchedConf), -1);
-      zkManager.setData(confVersionPath,
-          String.valueOf(System.currentTimeMillis()), -1);
     }
   }
 
@@ -196,9 +185,6 @@ public class ZKConfigurationStore extends YarnConfigurationStore {
       }
       zkManager.safeSetData(confStorePath, serializeObject(mapConf), -1,
           zkAcl, fencingNodePath);
-      zkManager.setData(confVersionPath,
-          String.valueOf(System.currentTimeMillis()), -1);
-
     }
     pendingMutation = null;
   }
@@ -227,11 +213,6 @@ public class ZKConfigurationStore extends YarnConfigurationStore {
     return null;
   }
 
-  @Override
-  public long getConfigVersion() throws Exception {
-    return Long.parseLong(zkManager.getStringData(confVersionPath));
-  }
-
   @Override
   public List<LogMutation> getConfirmedConfHistory(long fromId) {
     return null; // unimplemented

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMWSConsts.java

@@ -51,9 +51,6 @@ public final class RMWSConsts {
   /** Path for {@code RMWebServices#formatSchedulerConfiguration}. */
   public static final String FORMAT_SCHEDULER_CONF = "/scheduler-conf/format";
 
-  /** Path for {@code RMWebServices#getSchedulerConfigurationVersion}. */
-  public static final String SCHEDULER_CONF_VERSION = "/scheduler-conf/version";
-
   /** Path for {@code RMWebServiceProtocol#dumpSchedulerLogs}. */
   public static final String SCHEDULER_LOGS = "/scheduler/logs";
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/webapp/RMWebServices.java

@@ -2345,7 +2345,7 @@ public class RMWebServices extends WebServices implements RMWebServiceProtocol {
       }
     } else {
       return Response.status(Status.BAD_REQUEST)
-          .entity("Scheduler Configuration format only supported by " +
+          .entity("Configuration change only supported by " +
           "MutableConfScheduler.").build();
     }
   }
@@ -2435,38 +2435,6 @@ public class RMWebServices extends WebServices implements RMWebServiceProtocol {
     }
   }
 
-  @GET
-  @Path(RMWSConsts.SCHEDULER_CONF_VERSION)
-  @Produces({ MediaType.APPLICATION_JSON + "; " + JettyUtils.UTF_8,
-       MediaType.APPLICATION_XML + "; " + JettyUtils.UTF_8 })
-  public Response getSchedulerConfigurationVersion(@Context
-      HttpServletRequest hsr) throws AuthorizationException {
-    // Only admin user is allowed to get scheduler conf version
-    UserGroupInformation callerUGI = getCallerUserGroupInformation(hsr, true);
-    initForWritableEndpoints(callerUGI, true);
-
-    ResourceScheduler scheduler = rm.getResourceScheduler();
-    if (scheduler instanceof MutableConfScheduler
-        && ((MutableConfScheduler) scheduler).isConfigurationMutable()) {
-      MutableConfigurationProvider mutableConfigurationProvider =
-          ((MutableConfScheduler) scheduler).getMutableConfProvider();
-
-      try {
-        long configVersion = mutableConfigurationProvider
-            .getConfigVersion();
-        return Response.status(Status.OK).entity(configVersion).build();
-      } catch (Exception e) {
-        LOG.error("Exception thrown when fetching configuration version.", e);
-        return Response.status(Status.BAD_REQUEST).entity(e.getMessage())
-            .build();
-      }
-    } else {
-      return Response.status(Status.BAD_REQUEST)
-          .entity("Configuration Version only supported by "
-          + "MutableConfScheduler.").build();
-    }
-  }
-
   @GET
   @Path(RMWSConsts.CHECK_USER_ACCESS_TO_QUEUE)
   @Produces({ MediaType.APPLICATION_JSON + "; " + JettyUtils.UTF_8,

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/capacity/conf/TestZKConfigurationStore.java

@@ -137,21 +137,6 @@ public class TestZKConfigurationStore extends ConfigurationStoreBaseTest {
     assertNull(confStore.retrieve());
   }
 
-  @Test
-  public void testGetConfigurationVersion() throws Exception {
-    confStore.initialize(conf, schedConf, rmContext);
-    long v1 = confStore.getConfigVersion();
-    Thread.sleep(2000);
-    Map<String, String> update = new HashMap<>();
-    update.put("keyver", "valver");
-    YarnConfigurationStore.LogMutation mutation =
-        new YarnConfigurationStore.LogMutation(update, TEST_USER);
-    confStore.logMutation(mutation);
-    confStore.confirmMutation(true);
-    long v2 = confStore.getConfigVersion();
-    assertTrue(v2 > v1);
-  }
-
   @Test
   public void testPersistUpdatedConfiguration() throws Exception {
     confStore.initialize(conf, schedConf, rmContext);