Grokking the System Design Interview, Volume II
Vote

0% completed

​

Anatomy of a Read Operation

HDFS read process

We can outline the HDFS read process in seven steps.

  1. When an application opens a file for reading, the HDFS client starts a read request by calling the open() method on the Distributed FileSystem object. The client gives the file name, the start offset, and the length of the range to read.
  2. The Distributed FileSystem object works out which blocks it needs, based on that offset and range. It asks the NameNode for their locations.
  3. The NameNode holds the metadata for every block's location, and returns a list of blocks along with each replica's location

.....

.....

.....

Like the course? Get enrolled and start learning!

Reading Progress

0%

Vote for new content