will then look up in its internal table of contents to see where the first block (‘Block 1’) of
‘File1’ is stored. In this case, it happens to be DataNode 1.
The NameNode then forwards this request to the DataNode 1 to read the actual contents from
Block 1, and it is this content that is returned back to the client (Figure 3.6).
For example, three files are in HDFS with the size of a.txt (256 MB), b.txt (289 MB) and c.txt
(370 MB). Thus, HDFS will allocate a total of 8 blocks (default size of a block 128 MB) for these
three files. Here, a.txt will consume 2 blocks, b.txt and c.txt will absorb 3 blocks, respectively.
3.4.3 ...
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