DateTiered is fantastic if you've got time series, TTLed data. That means no updates to old data.
On Thu, Jun 4, 2015 at 10:58 AM Aiman Parvaiz <ai...@flipagram.com> wrote: > Hi everyone, > We are running a 10 node Cassandra 2.0.9 without vnode cluster. We are > running in to a issue where we are reading too many tombstones and hence > getting tons of WARN messages and some ERROR query aborted. > > cass-prod4 2015-06-04 14:38:34,307 WARN ReadStage: > <https://logentries.com/app/9f95dbd4#>1998 > SliceQueryFilter.collectReducedColumns - Read 46 live and 1560 tombstoned > cells in ABC.home_feed (see tombstone_warn_threshold). 100 columns was > requested, slices= <https://logentries.com/app/9f95dbd4#>[-], delInfo= > <https://logentries.com/app/9f95dbd4#>{deletedAt= > <https://logentries.com/app/9f95dbd4#>-9223372036854775808, localDeletion= > <https://logentries.com/app/9f95dbd4#>2147483647} > > cass-prod2 2015-05-31 12:55:55,331 ERROR ReadStage: > <https://logentries.com/app/9f95dbd4#>1953 > SliceQueryFilter.collectReducedColumns - Scanned over 100000 tombstones in > ABC.home_feed; query aborted (see tombstone_fail_threshold) > > As you can see all of this is happening for CF home_feed. This CF is > basically maintaining a feed with TTL set to 2592000 (30 days). > gc_grace_seconds for this CF is 864000 and its SizeTieredCompaction. > > Repairs have been running regularly and automatic compactions are > occurring normally too. > > I can definitely use some help here in how to tackle this issue. > > Up till now I have the following ideas: > > 1) I can make gc_grace_seconds to 0 and then do a manual compaction for > this CF and bump up the gc_grace again. > > 2) Make gc_grace 0, run manual compaction on this CF and leave gc_grace to > zero. In this case have to be careful in running repairs. > > 3) I am also considering moving to DateTier Compaction. > > What would be the best approach here for my feed case. Any help is > appreciated. > > Thanks > >
