There
are two types of writes in HDFS: posted and non-posted write. Posted Write is
when we write it and forget about it, without worrying about the
acknowledgement. It is similar to our traditional Indian post. In a Non-posted
Write, we wait for the acknowledgement. It is similar to the today’s courier
services. Naturally, non-posted write is more expensive than the posted write.
It is much more expensive, though both writes are asynchronous.
