I forgot to mention we are running Cassandra 1.1.2. Thanks, -Mike
On Sep 24, 2012, at 5:00 PM, Michael Theroux <mthero...@yahoo.com> wrote: > Hello, > > We are running into an unusual situation that I'm wondering if anyone has any > insight on. We've been running a Cassandra cluster for some time, with > compression enabled on one column family in which text documents are stored. > We enabled compression on the column family, utilizing the SnappyCompressor > and a 64k chunk length. > > It was recently discovered that Cassandra was reporting a compression ratio > of 0. I took a snapshot of the data and started a cassandra node in > isolation to investigate. > > Running nodetool scrub, or nodetool upgradesstables had little impact on the > amount of data that was being stored. > > I then disabled compression and ran nodetool upgradesstables on the column > family. Again, not impact on the data size stored. > > I then reenabled compression and ran nodetool upgradesstables on the column > family. This resulting in a 60% reduction in the data size stored, and > Cassandra reporting a compression ration of about .38. > > Any idea what is going on here? Obviously I can go through this process in > production to enable compression, however, any idea what is currently > happening and why new data does not appear to be compressed? > > Any insights are appreciated, > Thanks, > -Mike
