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From Sylvain Lebresne <sylv...@datastax.com>
Subject Re: possible 'coming back to life' bug with counters
Date Tue, 14 Jun 2011 18:40:23 GMT
As listed here: http://wiki.apache.org/cassandra/Counters, counter deletion is
provided as a convenience for permanent deletion of counters but, because
of the design of counters, it is never safe to issue an increment on a
counter that
has been deleted (that is, you will experience back to life behavior
sometimes in
that case).
More precisely, you'd have to wait long enough after a deletion to start
incrementing the counter again. But in the worst cases, long enough is something
like gc_grace_seconds + major compaction.

This is *not* something that is likely to change anytime soon (I don't
think this is
fixable with the current design for counters).

--
Sylvain

On Sat, Jun 11, 2011 at 3:54 AM, David Hawthorne <dhawth@3crowd.com> wrote:
> Please take a look at this thread over in the hector-users mailing list:
> http://groups.google.com/group/hector-users/browse_thread/thread/99835159b9ea1766
> It looks as if the deleted columns are coming back to life when they
> shouldn't be.
> I don't want to open a bug on something if it's already got one that I just
> couldn't find when I scanned the list of open bugs.
> I'm using hector 0.8 against cassandra 0.8 release.  I can give you whatever
> logs or files you'd like.

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