hadoop-common-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "FAQ" by KonstantinShvachko
Date Fri, 27 Jun 2008 19:51:47 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change notification.

The following page has been changed by KonstantinShvachko:

  The only purpose of the secondary name-node is to perform periodic checkpoints.
  The secondary name-node periodically downloads current name-node image and edits log files,
  joins them into new image and uploads the new image back to the (primary and the only) name-node.
+ See [http://hadoop.apache.org/core/docs/current/hdfs_user_guide.html#Secondary+Namenode
  So if the name-node fails and you can restart it on the same physical node then there is
no need 
  to shutdown data-nodes, just the name-node need to be restarted.
@@ -303, +304 @@

  GridGain does not support data intensive jobs. For more details, see HadoopVsGridGain.
+ [[BR]]
+ [[Anchor(21)]]
+ '''21. [#21 HDFS. Can I have multiple files in HDFS use different block sizes?]'''
+ Yes. HDFS provides api to specify block size when you create a file. [[BR]]
+ See
+ [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/fs/FileSystem.html#create(org.apache.hadoop.fs.Path,%20boolean,%20int,%20short,%20long)
FileSystem.create(Path, overwrite, bufferSize, replication, blockSize, progress)]

View raw message