Convert properties in FIXED_PROPERTIES to be non-fixed

core/src/main/java/org/apache/accumulo/core/conf/Property.java

@@ -1611,16 +1611,15 @@ public static boolean isValidTablePropertyKey(String key) {
       // MANAGER options
       MANAGER_THREADCHECK, MANAGER_FATE_METRICS_MIN_UPDATE_INTERVAL, MANAGER_METADATA_SUSPENDABLE,
       MANAGER_STARTUP_TSERVER_AVAIL_MIN_COUNT, MANAGER_STARTUP_TSERVER_AVAIL_MAX_WAIT,
-      MANAGER_CLIENTPORT, MANAGER_MINTHREADS, MANAGER_MINTHREADS_TIMEOUT,
-      MANAGER_RECOVERY_WAL_EXISTENCE_CACHE_TIME, MANAGER_COMPACTION_SERVICE_PRIORITY_QUEUE_SIZE,
-      MANAGER_TABLET_REFRESH_MINTHREADS, MANAGER_TABLET_REFRESH_MAXTHREADS,
-      MANAGER_TABLET_MERGEABILITY_INTERVAL, MANAGER_FATE_CONDITIONAL_WRITER_THREADS_MAX,
+      MANAGER_CLIENTPORT, MANAGER_MINTHREADS_TIMEOUT, MANAGER_RECOVERY_WAL_EXISTENCE_CACHE_TIME,
+      MANAGER_COMPACTION_SERVICE_PRIORITY_QUEUE_SIZE, MANAGER_TABLET_MERGEABILITY_INTERVAL,
+      MANAGER_FATE_CONDITIONAL_WRITER_THREADS_MAX,
 
       // SSERV options
       SSERV_CACHED_TABLET_METADATA_REFRESH_PERCENT, SSERV_THREADCHECK, SSERV_CLIENTPORT,
       SSERV_PORTSEARCH, SSERV_DATACACHE_SIZE, SSERV_INDEXCACHE_SIZE, SSERV_SUMMARYCACHE_SIZE,
       SSERV_DEFAULT_BLOCKSIZE, SSERV_SCAN_REFERENCE_EXPIRATION_TIME,
-      SSERV_CACHED_TABLET_METADATA_EXPIRATION, SSERV_MINTHREADS, SSERV_MINTHREADS_TIMEOUT,
+      SSERV_CACHED_TABLET_METADATA_EXPIRATION, SSERV_MINTHREADS_TIMEOUT,
       SSERV_WAL_SORT_MAX_CONCURRENT, SSERV_GROUP_NAME,
 
       // TSERV options
@@ -1631,8 +1630,8 @@ public static boolean isValidTablePropertyKey(String key) {
       TSERV_LOG_BUSY_TABLETS_COUNT, TSERV_LOG_BUSY_TABLETS_INTERVAL, TSERV_WAL_SORT_MAX_CONCURRENT,
       TSERV_SLOW_FILEPERMIT_MILLIS, TSERV_WAL_BLOCKSIZE, TSERV_CLIENTPORT, TSERV_PORTSEARCH,
       TSERV_DATACACHE_SIZE, TSERV_INDEXCACHE_SIZE, TSERV_SUMMARYCACHE_SIZE, TSERV_DEFAULT_BLOCKSIZE,
-      TSERV_MINTHREADS, TSERV_MINTHREADS_TIMEOUT, TSERV_NATIVEMAP_ENABLED, TSERV_MAXMEM,
-      TSERV_SCAN_MAX_OPENFILES, TSERV_ONDEMAND_UNLOADER_INTERVAL, TSERV_GROUP_NAME,
+      TSERV_MINTHREADS_TIMEOUT, TSERV_NATIVEMAP_ENABLED, TSERV_MAXMEM, TSERV_SCAN_MAX_OPENFILES,
+      TSERV_ONDEMAND_UNLOADER_INTERVAL, TSERV_GROUP_NAME,
 
       // GC options
       GC_CANDIDATE_BATCH_SIZE, GC_CYCLE_START, GC_PORT,
@@ -1643,8 +1642,7 @@ public static boolean isValidTablePropertyKey(String key) {
 
       // COMPACTOR options
       COMPACTOR_CANCEL_CHECK_INTERVAL, COMPACTOR_CLIENTPORT, COMPACTOR_THREADCHECK,
-      COMPACTOR_PORTSEARCH, COMPACTOR_MINTHREADS, COMPACTOR_MINTHREADS_TIMEOUT,
-      COMPACTOR_GROUP_NAME,
+      COMPACTOR_PORTSEARCH, COMPACTOR_MINTHREADS_TIMEOUT, COMPACTOR_GROUP_NAME,
 
       // COMPACTION_COORDINATOR options
       COMPACTION_COORDINATOR_DEAD_COMPACTOR_CHECK_INTERVAL,

core/src/main/java/org/apache/accumulo/core/util/threads/ThreadPools.java

@@ -219,6 +219,43 @@ public static void ensureRunning(ScheduledFuture<?> future, String message) {
     }
   }
 
+  /**
+   * Resize ThreadPoolExecutor based on current value of minThreads
+   *
+   * @param pool the ThreadPoolExecutor to modify
+   * @param minThreads supplier of minThreads value
+   * @param poolName name of the thread pool
+   */
+  public static void resizeCorePool(final ThreadPoolExecutor pool, final IntSupplier minThreads,
+      String poolName) {
+    int count = pool.getPoolSize();
+    int newCount = minThreads.getAsInt();
+    if (count == newCount) {
+      return;
+    }
+    LOG.info("Changing min threads for {} from {} to {}", poolName, count, newCount);
+    if (newCount < count) {
+      pool.setCorePoolSize(newCount);
+    } else {
+      if (newCount > pool.getMaximumPoolSize()) {
+        pool.setMaximumPoolSize(newCount);
+      }
+      pool.setCorePoolSize(newCount);
+    }
+  }
+
+  /**
+   * Resize ThreadPoolExecutor based on current value of Property p
+   *
+   * @param pool the ThreadPoolExecutor to modify
+   * @param conf the AccumuloConfiguration
+   * @param p the property to base the size from
+   */
+  public static void resizeCorePool(final ThreadPoolExecutor pool, final AccumuloConfiguration conf,
+      final Property p) {
+    resizeCorePool(pool, () -> conf.getCount(p), p.getKey());
+  }
+
   /**
    * Resize ThreadPoolExecutor based on current value of maxThreads
    *

server/manager/src/main/java/org/apache/accumulo/manager/Manager.java

@@ -50,6 +50,7 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
@@ -262,6 +263,7 @@ void setTserverStatus(LiveTServersSnapshot snapshot,
   private final long timeToCacheRecoveryWalExistence;
   private ExecutorService tableInformationStatusPool = null;
   private ThreadPoolExecutor tabletRefreshThreadPool;
+  private ScheduledExecutorService refreshCheckerScheduler;
 
   private final TabletStateStore rootTabletStore;
   private final TabletStateStore metadataTabletStore;
@@ -905,6 +907,24 @@ private void checkForHeldServer(SortedMap<TServerInstance,TabletServerStatus> ts
     return info;
   }
 
+  private class RefreshThreads implements Runnable {
+    @Override
+    public void run() {
+      ThreadPools.resizeCorePool(tabletRefreshThreadPool, getConfiguration(),
+          Property.MANAGER_TABLET_REFRESH_MINTHREADS);
+      ThreadPools.resizePool(tabletRefreshThreadPool, getConfiguration(),
+          Property.MANAGER_TABLET_REFRESH_MAXTHREADS);
+
+    }
+  }
+
+  public void startRefreshChecker() {
+    refreshCheckerScheduler = ThreadPools.getServerThreadPools().createScheduledExecutorService(1,
+        "ManagerTabletRefreshThreadsExecutor");
+    ThreadPools.watchNonCriticalScheduledTask(
+        refreshCheckerScheduler.scheduleAtFixedRate(new RefreshThreads(), 5, 5, MINUTES));
+  }
+
   @Override
   public void run() {
     final ServerContext context = getContext();
@@ -968,6 +988,8 @@ public void run() {
         .numMaxThreads(getConfiguration().getCount(Property.MANAGER_TABLET_REFRESH_MAXTHREADS))
         .build();
 
+    startRefreshChecker();
+
     Thread statusThread = Threads.createCriticalThread("Status Thread", new StatusThread());
     statusThread.start();
 
@@ -1235,6 +1257,7 @@ boolean canSuspendTablets() {
 
     tableInformationStatusPool.shutdownNow();
     tabletRefreshThreadPool.shutdownNow();
+    refreshCheckerScheduler.shutdown();
 
     compactionCoordinator.shutdown();