HDFS-17063. Support to configure different capacity reserved for each disk of DataNode. (#5793). Contributed by QI Jiale.

Reviewed-by : Tao Li <tomscut@apache.org>
Signed-off-by: He Xiaoqiao <hexiaoqiao@apache.org>

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/FsVolumeImpl.java

@@ -171,7 +171,8 @@ public class FsVolumeImpl implements FsVolumeSpi {
     this.usage = usage;
     if (this.usage != null) {
       reserved = new ReservedSpaceCalculator.Builder(conf)
-          .setUsage(this.usage).setStorageType(storageType).build();
+          .setUsage(this.usage).setStorageType(storageType)
+          .setDir(currentDir != null ? currentDir.getParent() : "NULL").build();
       boolean fixedSizeVolume = conf.getBoolean(
           DFSConfigKeys.DFS_DATANODE_FIXED_VOLUME_SIZE_KEY,
           DFSConfigKeys.DFS_DATANODE_FIXED_VOLUME_SIZE_DEFAULT);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/ReservedSpaceCalculator.java

@@ -46,6 +46,8 @@ public abstract class ReservedSpaceCalculator {
     private DF usage;
     private StorageType storageType;
 
+    private String dir;
+
     public Builder(Configuration conf) {
       this.conf = conf;
     }
@@ -61,6 +63,11 @@ public abstract class ReservedSpaceCalculator {
       return this;
     }
 
+    public Builder setDir(String newDir) {
+      this.dir = newDir;
+      return this;
+    }
+
     ReservedSpaceCalculator build() {
       try {
         Class<? extends ReservedSpaceCalculator> clazz = conf.getClass(
@@ -69,10 +76,10 @@ public abstract class ReservedSpaceCalculator {
             ReservedSpaceCalculator.class);
 
         Constructor constructor = clazz.getConstructor(
-            Configuration.class, DF.class, StorageType.class);
+            Configuration.class, DF.class, StorageType.class, String.class);
 
         return (ReservedSpaceCalculator) constructor.newInstance(
-            conf, usage, storageType);
+            conf, usage, storageType, dir);
       } catch (Exception e) {
         throw new IllegalStateException(
             "Error instantiating ReservedSpaceCalculator", e);
@@ -84,20 +91,30 @@ public abstract class ReservedSpaceCalculator {
   private final Configuration conf;
   private final StorageType storageType;
 
+  private final String dir;
+
   ReservedSpaceCalculator(Configuration conf, DF usage,
-      StorageType storageType) {
+      StorageType storageType, String dir) {
     this.usage = usage;
     this.conf = conf;
     this.storageType = storageType;
+    this.dir = dir;
   }
 
   DF getUsage() {
     return usage;
   }
 
+  String getDir() {
+    return dir;
+  }
+
   long getReservedFromConf(String key, long defaultValue) {
-    return conf.getLong(key + "." + StringUtils.toLowerCase(
-        storageType.toString()), conf.getLongBytes(key, defaultValue));
+    return conf.getLong(
+        key + "." + getDir() + "." + StringUtils.toLowerCase(storageType.toString()),
+        conf.getLong(key + "." + getDir(),
+            conf.getLong(key + "." + StringUtils.toLowerCase(storageType.toString()),
+                conf.getLongBytes(key, defaultValue))));
   }
 
   /**
@@ -117,8 +134,8 @@ public abstract class ReservedSpaceCalculator {
     private final long reservedBytes;
 
     public ReservedSpaceCalculatorAbsolute(Configuration conf, DF usage,
-        StorageType storageType) {
-      super(conf, usage, storageType);
+        StorageType storageType, String dir) {
+      super(conf, usage, storageType, dir);
       this.reservedBytes = getReservedFromConf(DFS_DATANODE_DU_RESERVED_KEY,
           DFS_DATANODE_DU_RESERVED_DEFAULT);
     }
@@ -138,8 +155,8 @@ public abstract class ReservedSpaceCalculator {
     private final long reservedPct;
 
     public ReservedSpaceCalculatorPercentage(Configuration conf, DF usage,
-        StorageType storageType) {
-      super(conf, usage, storageType);
+        StorageType storageType, String dir) {
+      super(conf, usage, storageType, dir);
       this.reservedPct = getReservedFromConf(
           DFS_DATANODE_DU_RESERVED_PERCENTAGE_KEY,
           DFS_DATANODE_DU_RESERVED_PERCENTAGE_DEFAULT);
@@ -162,8 +179,8 @@ public abstract class ReservedSpaceCalculator {
     private final long reservedPct;
 
     public ReservedSpaceCalculatorConservative(Configuration conf, DF usage,
-        StorageType storageType) {
-      super(conf, usage, storageType);
+        StorageType storageType, String dir) {
+      super(conf, usage, storageType, dir);
       this.reservedBytes = getReservedFromConf(DFS_DATANODE_DU_RESERVED_KEY,
           DFS_DATANODE_DU_RESERVED_DEFAULT);
       this.reservedPct = getReservedFromConf(
@@ -197,8 +214,8 @@ public abstract class ReservedSpaceCalculator {
     private final long reservedPct;
 
     public ReservedSpaceCalculatorAggressive(Configuration conf, DF usage,
-        StorageType storageType) {
-      super(conf, usage, storageType);
+        StorageType storageType, String dir) {
+      super(conf, usage, storageType, dir);
       this.reservedBytes = getReservedFromConf(DFS_DATANODE_DU_RESERVED_KEY,
           DFS_DATANODE_DU_RESERVED_DEFAULT);
       this.reservedPct = getReservedFromConf(

hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml

@@ -397,12 +397,19 @@
   <name>dfs.datanode.du.reserved</name>
   <value>0</value>
   <description>Reserved space in bytes per volume. Always leave this much space free for non dfs use.
+      Specific directory based reservation is supported. The property can be followed with directory
+      name which is set at 'dfs.datanode.data.dir'. For example, reserved space for /data/hdfs1/data
+      can be configured using property 'dfs.datanode.du.reserved./data/hdfs1/data'. If specific directory
+      reservation is not configured then dfs.datanode.du.reserved will be used.
       Specific storage type based reservation is also supported. The property can be followed with
       corresponding storage types ([ssd]/[disk]/[archive]/[ram_disk]/[nvdimm]) for cluster with heterogeneous storage.
       For example, reserved space for RAM_DISK storage can be configured using property
       'dfs.datanode.du.reserved.ram_disk'. If specific storage type reservation is not configured
       then dfs.datanode.du.reserved will be used. Support multiple size unit suffix(case insensitive),
-      as described in dfs.blocksize.
+      as described in dfs.blocksize. Use directory name and storage type based reservation at the
+      same time is also allowed if both are configured.
+      Property priority example: dfs.datanode.du.reserved./data/hdfs1/data.ram_disk >
+      dfs.datanode.du.reserved./data/hdfs1/data > dfs.datanode.du.reserved.ram_disk > dfs.datanode.du.reserved
       Note: In case of using tune2fs to set reserved-blocks-percentage, or other filesystem tools,
       then you can possibly run into out of disk errors because hadoop will not check those
       external tool configurations.
@@ -414,12 +421,19 @@
   <value>0</value>
   <description>Reserved space in percentage. Read dfs.datanode.du.reserved.calculator to see
     when this takes effect. The actual number of bytes reserved will be calculated by using the
-    total capacity of the data directory in question. Specific storage type based reservation
+    total capacity of the data directory in question. Specific directory based reservation is
+    supported. The property can be followed with directory name which is set at 'dfs.datanode.data.dir'.
+    For example, reserved percentage space for /data/hdfs1/data can be configured using property
+    'dfs.datanode.du.reserved.pct./data/hdfs1/data'. If specific directory reservation is not
+    configured then dfs.datanode.du.reserved.pct will be used. Specific storage type based reservation
     is also supported. The property can be followed with corresponding storage types
     ([ssd]/[disk]/[archive]/[ram_disk]/[nvdimm]) for cluster with heterogeneous storage.
     For example, reserved percentage space for RAM_DISK storage can be configured using property
     'dfs.datanode.du.reserved.pct.ram_disk'. If specific storage type reservation is not configured
-    then dfs.datanode.du.reserved.pct will be used.
+    then dfs.datanode.du.reserved.pct will be used. Use directory and storage type based reservation
+    is also allowed if both are configured.
+    Priority example: dfs.datanode.du.reserved.pct./data/hdfs1/data.ram_disk > dfs.datanode.du.reserved.pct./data/hdfs1/data
+    > dfs.datanode.du.reserved.pct.ram_disk > dfs.datanode.du.reserved.pct
   </description>
 </property>
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/impl/TestReservedSpaceCalculator.java

@@ -168,6 +168,55 @@ public class TestReservedSpaceCalculator {
     checkReserved(StorageType.ARCHIVE, 100000, 5000);
   }
 
+  @Test
+  public void testReservedSpaceAbsolutePerDir() {
+    conf.setClass(DFS_DATANODE_DU_RESERVED_CALCULATOR_KEY, ReservedSpaceCalculatorAbsolute.class,
+        ReservedSpaceCalculator.class);
+
+    String dir1 = "/data/hdfs1/data";
+    String dir2 = "/data/hdfs2/data";
+    String dir3 = "/data/hdfs3/data";
+
+    conf.setLong(DFS_DATANODE_DU_RESERVED_KEY + "." + dir1 + ".ssd", 900);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_KEY + "." + dir1, 1800);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_KEY + "." + dir2, 2700);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_KEY + ".ssd", 3600);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_KEY, 4500);
+
+    checkReserved(StorageType.SSD, 10000, 900, dir1);
+    checkReserved(StorageType.DISK, 10000, 1800, dir1);
+    checkReserved(StorageType.SSD, 10000, 2700, dir2);
+    checkReserved(StorageType.DISK, 10000, 2700, dir2);
+    checkReserved(StorageType.SSD, 10000, 3600, dir3);
+    checkReserved(StorageType.DISK, 10000, 4500, dir3);
+  }
+
+  @Test
+  public void testReservedSpacePercentagePerDir() {
+    conf.setClass(DFS_DATANODE_DU_RESERVED_CALCULATOR_KEY,
+            ReservedSpaceCalculatorPercentage.class,
+            ReservedSpaceCalculator.class);
+
+    String dir1 = "/data/hdfs1/data";
+    String dir2 = "/data/hdfs2/data";
+    String dir3 = "/data/hdfs3/data";
+
+    // Set percentage reserved values for different directories
+    conf.setLong(DFS_DATANODE_DU_RESERVED_PERCENTAGE_KEY + "." + dir1 + ".ssd", 20);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_PERCENTAGE_KEY + "." + dir1, 10);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_PERCENTAGE_KEY + "." + dir2, 25);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_PERCENTAGE_KEY + ".ssd", 30);
+    conf.setLong(DFS_DATANODE_DU_RESERVED_PERCENTAGE_KEY, 40);
+
+    // Verify reserved space calculations for different directories and storage types
+    checkReserved(StorageType.SSD, 10000, 2000, dir1);
+    checkReserved(StorageType.DISK, 10000, 1000, dir1);
+    checkReserved(StorageType.SSD, 10000, 2500, dir2);
+    checkReserved(StorageType.DISK, 10000, 2500, dir2);
+    checkReserved(StorageType.SSD, 10000, 3000, dir3);
+    checkReserved(StorageType.DISK, 10000, 4000, dir3);
+  }
+
   @Test(expected = IllegalStateException.class)
   public void testInvalidCalculator() {
     conf.set(DFS_DATANODE_DU_RESERVED_CALCULATOR_KEY, "INVALIDTYPE");
@@ -179,10 +228,15 @@ public class TestReservedSpaceCalculator {
 
   private void checkReserved(StorageType storageType,
       long totalCapacity, long reservedExpected) {
+    checkReserved(storageType, totalCapacity, reservedExpected, "NULL");
+  }
+
+  private void checkReserved(StorageType storageType,
+      long totalCapacity, long reservedExpected, String dir) {
     when(usage.getCapacity()).thenReturn(totalCapacity);
 
     reserved = new ReservedSpaceCalculator.Builder(conf).setUsage(usage)
-        .setStorageType(storageType).build();
+        .setStorageType(storageType).setDir(dir).build();
     assertEquals(reservedExpected, reserved.getReserved());
   }
 }