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Subject: Cassandra 1.0 - is disk seek required to access SSTable metadata
From: Maciej Miklas <mac.miklas@gmail.com>
To: user@cassandra.apache.org
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--047d7b6d7e00cdb10104c6bca731
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Hi all,

older Cassandra versions had to read columns from each SSTable with
positive bloom filter in order to find recent value.
This was optimized with: Improve read performance in update-intensive
workload <https://issues.apache.org/jira/browse/CASSANDRA-2498>
Now each SSTable has metadata - SSTableMetadata.

Bloom filter is stored in RAM, but what about metadata?
Is disk seek required to access it?

Thanks,
Maciej

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Hi all,<br>
<br>
older Cassandra versions had to read columns from each SSTable with<br>
positive bloom filter in order to find recent value.<br>
This was optimized with: Improve read performance in update-intensive<br>
workload &lt;<a href="https://issues.apache.org/jira/browse/CASSANDRA-2498" target="_blank">https://issues.apache.org/jira/browse/CASSANDRA-2498</a>&gt;<br>
Now each SSTable has metadata - SSTableMetadata.<br>
<br>
Bloom filter is stored in RAM, but what about metadata?<br>
Is disk seek required to access it?<br>
<br>
Thanks,<br>
Maciej

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