big-data/hadoop
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

HDFS-10326. Disable setting tcp socket send/receive buffers for write pipelines. Contributed by Daryn Sharp.

Browse Source
This commit is contained in:
Haohui Mai 2017-08-08 14:58:11 -07:00
parent e0c24145d2
commit 71b8dda4f6
3 changed files with 20 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/HdfsConstants.java
View File

@ -48,8 +48,8 @@ public final class HdfsConstants {
public static final byte COLD_STORAGE_POLICY_ID = 2; public static final byte COLD_STORAGE_POLICY_ID = 2;
public static final String COLD_STORAGE_POLICY_NAME = "COLD"; public static final String COLD_STORAGE_POLICY_NAME = "COLD";
// TODO should be conf injected? public static final int DEFAULT_DATA_SOCKET_SIZE = 0;
public static final int DEFAULT_DATA_SOCKET_SIZE = 128 * 1024;
/** /**
* A special path component contained in the path for a snapshot file/dir * A special path component contained in the path for a snapshot file/dir
*/ */

9
hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
View File

@ -2545,13 +2545,14 @@
<property> <property>
<name>dfs.client.socket.send.buffer.size</name> <name>dfs.client.socket.send.buffer.size</name>
<value>131072</value> <value>0</value>
<description> <description>
Socket send buffer size for a write pipeline in DFSClient side. Socket send buffer size for a write pipeline in DFSClient side.
This may affect TCP connection throughput. This may affect TCP connection throughput.
If it is set to zero or negative value, If it is set to zero or negative value,
no buffer size will be set explicitly, no buffer size will be set explicitly,
thus enable tcp auto-tuning on some system. thus enable tcp auto-tuning on some system.
The default value is 0.
</description> </description>
</property> </property>
@ -3025,23 +3026,25 @@
<property> <property>
<name>dfs.datanode.transfer.socket.send.buffer.size</name> <name>dfs.datanode.transfer.socket.send.buffer.size</name>
<value>131072</value> <value>0</value>
<description> <description>
Socket send buffer size for DataXceiver (mirroring packets to downstream Socket send buffer size for DataXceiver (mirroring packets to downstream
in pipeline). This may affect TCP connection throughput. in pipeline). This may affect TCP connection throughput.
If it is set to zero or negative value, no buffer size will be set If it is set to zero or negative value, no buffer size will be set
explicitly, thus enable tcp auto-tuning on some system. explicitly, thus enable tcp auto-tuning on some system.
The default value is 0.
</description> </description>
</property> </property>
<property> <property>
<name>dfs.datanode.transfer.socket.recv.buffer.size</name> <name>dfs.datanode.transfer.socket.recv.buffer.size</name>
<value>131072</value> <value>0</value>
<description> <description>
Socket receive buffer size for DataXceiver (receiving packets from client Socket receive buffer size for DataXceiver (receiving packets from client
during block writing). This may affect TCP connection throughput. during block writing). This may affect TCP connection throughput.
If it is set to zero or negative value, no buffer size will be set If it is set to zero or negative value, no buffer size will be set
explicitly, thus enable tcp auto-tuning on some system. explicitly, thus enable tcp auto-tuning on some system.
The default value is 0.
</description> </description>
</property> </property>

18
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSClientSocketSize.java
View File

@ -30,7 +30,6 @@
import java.io.IOException; import java.io.IOException;
import java.net.Socket; import java.net.Socket;
import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT;
import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY; import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_KEY;
import static org.junit.Assert.assertTrue; import static org.junit.Assert.assertTrue;
@ -42,15 +41,16 @@ public class TestDFSClientSocketSize {
} }
/** /**
* The setting of socket send buffer size in * Test that the send buffer size default value is 0, in which case the socket
* {@link java.net.Socket#setSendBufferSize(int)} is only a hint. Actual * will use a TCP auto-tuned value.
* value may differ. We just sanity check that it is somewhere close.
*/ */
@Test @Test
public void testDefaultSendBufferSize() throws IOException { public void testDefaultSendBufferSize() throws IOException {
assertTrue("Send buffer size should be somewhere near default.", final int sendBufferSize = getSendBufferSize(new Configuration());
getSendBufferSize(new Configuration()) >= LOG.info("If not specified, the auto tuned send buffer size is: {}",
DFS_CLIENT_SOCKET_SEND_BUFFER_SIZE_DEFAULT / 2); sendBufferSize);
assertTrue("Send buffer size should be non-negative value which is " +
"determined by system (kernel).", sendBufferSize > 0);
} }
/** /**
@ -73,6 +73,10 @@ public void testSpecifiedSendBufferSize() throws IOException {
sendBufferSize1 > sendBufferSize2); sendBufferSize1 > sendBufferSize2);
} }
/**
* Test that if the send buffer size is 0, the socket will use a TCP
* auto-tuned value.
*/
@Test @Test
public void testAutoTuningSendBufferSize() throws IOException { public void testAutoTuningSendBufferSize() throws IOException {
final Configuration conf = new Configuration(); final Configuration conf = new Configuration();