Re: Why datanode does a flush to disk after receiving a packet

Nope, flush just flushes the java side buffer to the Linux buffer cache -- not all the way to the media. Hsync is the API that will eventually go all the way to disk, but it has not yet been implemented. -Todd On Wednesday, November 10, 2010, Thanh Do wrote: > Or another way to rephase my quest

Re: Why datanode does a flush to disk after receiving a packet

Or another way to rephase my question: does data.flush and checksumOut.flush guarantee data be synchronized with underlying disk, just like fsync(). Thanks Thanh On Wed, Nov 10, 2010 at 10:26 PM, Thanh Do wrote: > Hi all, > > After reading the appenddesign3.pdf in HDFS-256, > and looking at the

Why datanode does a flush to disk after receiving a packet

Hi all, After reading the appenddesign3.pdf in HDFS-256, and looking at the BlockReceiver.java code in 0.21.0, I am confused by the following. The document says that: *For each packet, a DataNode in the pipeline has to do 3 things. 1. Stream data a. Receive data from the upstream DataNode o

Build failed in Hudson: Hadoop-Hdfs-trunk #483

See -- [...truncated 761730 lines...] [junit] at sun.nio.ch.SocketDispatcher.write(SocketDispatcher.java:29) [junit] at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:104)