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From preetika tyagi <preetikaty...@gmail.com>
Subject question on maximum disk seeks
Date Mon, 20 Mar 2017 20:17:56 GMT
I'm trying to understand the maximum number of disk seeks required in a
read operation in Cassandra. I looked at several online articles including
this one:
https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlAboutReads.html

As per my understanding, two disk seeks are required in the worst case. One
is for reading the partition index and another is to read the actual data
from the compressed partition. The index of the data in compressed
partitions is obtained from the compression offset tables (which is stored
in memory). Am I on the right track here? Will there ever be a case when
more than 1 disk seek is required to read the data?

Thanks,

Preetika

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