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Date: Fri, 26 Feb 2010 11:22:57 -0600
Message-ID: <1c6fcff1002260922m12fbcc1dg97048ec1bc727c39@mail.gmail.com>
Subject: Commit log changes in 0.7
From: Gary Dusbabek <gdusbabek@gmail.com>
To: cassandra-dev@incubator.apache.org
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The commit log currently has a header section whose size is constant,
but is a function of the total number of defined column families.
This isn't going to work with CASSANDRA-44 where CFs can be added or
removed on the fly.  I see two options:

1.  hard code the size of the header to accommodate a maximum number
of CFs.  I don't like this approach because it imposes a hard limit.
2.  move the header into its own file.  I don't like this because it
adds complexity.

Any better other ideas?

Some background:  the data stored in the header indicates a) which CFs
are 'dirty' and b) log replay offsets for each CF.