HBASE-27129 Add a config that allows us to configure region-level sto…

…rage policies (#4547)

Co-authored-by: Tang Tianhang <tianhang.tang@shopee.com>
Signed-off-by: Duo Zhang <zhangduo@apache.org>

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java

@@ -256,6 +256,9 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
   public static final String SPLIT_IGNORE_BLOCKING_ENABLED_KEY =
     "hbase.hregion.split.ignore.blocking.enabled";
 
+  public static final String REGION_STORAGE_POLICY_KEY = "hbase.hregion.block.storage.policy";
+  public static final String DEFAULT_REGION_STORAGE_POLICY = "NONE";
+
   /**
    * This is for for using HRegion as a local storage, where we may put the recovered edits in a
    * special place. Once this is set, we will only replay the recovered edits under this directory
@@ -980,6 +983,9 @@ private long initializeRegionInternals(final CancelableProgressable reporter,
       coprocessorHost.preOpen();
     }
 
+    String policyName = this.conf.get(REGION_STORAGE_POLICY_KEY, DEFAULT_REGION_STORAGE_POLICY);
+    this.fs.setStoragePolicy(policyName.trim());
+
     // Write HRI to a file in case we need to recover hbase:meta
     // Only the primary replica should write .regioninfo
     if (this.getRegionInfo().getReplicaId() == RegionInfo.DEFAULT_REPLICA_ID) {

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionFileSystem.java

@@ -225,6 +225,20 @@ public void setStoragePolicy(String familyName, String policyName) {
     CommonFSUtils.setStoragePolicy(this.fs, getStoreDir(familyName), policyName);
   }
 
+  /**
+   * Set storage policy for a whole region. <br>
+   * <i>"LAZY_PERSIST"</i>, <i>"ALL_SSD"</i>, <i>"ONE_SSD"</i>, <i>"HOT"</i>, <i>"WARM"</i>,
+   * <i>"COLD"</i> <br>
+   * <br>
+   * See {@link org.apache.hadoop.hdfs.protocol.HdfsConstants} for more details.
+   * @param policyName The name of the storage policy: 'HOT', 'COLD', etc. See hadoop 2.6+
+   *                   org.apache.hadoop.hdfs.protocol.HdfsConstants for possible list e.g 'COLD',
+   *                   'WARM', 'HOT', 'ONE_SSD', 'ALL_SSD', 'LAZY_PERSIST'.
+   */
+  public void setStoragePolicy(String policyName) {
+    CommonFSUtils.setStoragePolicy(this.fs, getRegionDir(), policyName);
+  }
+
   /**
    * Get the storage policy of the directory of CF.
    * @param familyName The name of column family.