Reading
is done in parallel because by doing so we can access the data fast. But we do
not perform the write operation in parallel. The reason is that if we perform
the write operation in parallel, then it might result in data inconsistency.
For example, you have a file and two nodes are trying to write data into the
file in parallel, then the first node does not know what the second node has
written and vice-versa. So, this makes it confusing which data to be stored and
accessed.
