cassandra-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Peter Schuller <>
Subject Re: Atomically adding a column to columns_
Date Mon, 27 Sep 2010 20:54:29 GMT
> Function addColumn at class SuperColumn tries to atomically add a column to
> the concurrent collection “columns_” using the following code:

Deletions in Cassandra involve an insertion of a tombstone rather than
actual column deletion.

In the case of this bit of code, I believe, and I am not speaking
authoritatively, the removal only happens in (1) the read path when
filtering results (on presumably query-local data) and (2) during
compaction (on presumably compaction-local data). I did browse through
the various callers which seemed to confirm that this was the case. In
other words, I do not believe the remove() code path should not ever
be taken concurrently with insertions (by design, and not by

Anyone care to confirm/deny?

/ Peter Schuller

View raw message