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From: Omid Aladini <omidaladini@gmail.com>
Date: Tue, 11 Sep 2012 23:50:07 +0200
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Subject: Re: Assertions running Cleanup on a 3-node cluster with Cassandra
 1.1.4 and LCS
To: user@cassandra.apache.org
Content-Type: text/plain; charset=UTF-8

On Tue, Sep 11, 2012 at 8:33 PM, Janne Jalkanen
<janne.jalkanen@ecyrd.com> wrote:
>
>> A bug in Cassandra 1.1.2 and earlier could cause out-of-order sstables
>> and inter-level overlaps in CFs with Leveled Compaction. Your sstables
>> generated with 1.1.3 and later should not have this issue [1] [2].
>
> Does this mean that LCS on 1.0.x should be considered unsafe to
> use? I'm using them for semi-wide frequently-updated CounterColumns
> and they're performing much better on LCS than on STCS.

That's true. "Unsafe" in the sense that your data might not be in the
right shape with respect to order of keys in sstables and LCS's
properties and you might need to offline-scrub when you upgrade to the
latest 1.1.x.

>> In case you have old Leveled-compacted sstables (generated with 1.1.2
>> or earlier. including 1.0.x) you need to run offline scrub using
>> Cassandra 1.1.4 or later via /bin/sstablescrub command so it'll fix
>> out-of-order sstables and inter-level overlaps caused by previous
>> versions of LCS. You need to take nodes down in order to run offline
>> scrub.
>
> The  1.1.5 README does not mention this. Should it?

The fix was released on 1.1.3 (LCS fix) and 1.1.4 (offline scrub) and
I agree it would be helpful to have it on NEWS.txt.

Cheers,
Omid

> /Janne
>