Hi, I think you got it, this is probably the way to go:
> And if it so, forceUserdefinedcompaction or setting > unchecked_tombstone_compactions > to true wont help either as tombstones are less than 20% and not much disk > would be recovered. But if you have less than 20% tombstones in there I am not sure that compacting those tables will help anyhow. It's probably time to add capacity (nodes, as you can't add disks). If you still want to give it a try, set the unchecked_tombstone_compactions to true and the ratio to10% and see how it goes. An other option to have better control on disk size and being able to use up to 70% - 80% of the disk, then LCS might be a good option, if it fits with your use case. C*heers, ----------------------- Alain Rodriguez - [email protected] France The Last Pickle - Apache Cassandra Consulting http://www.thelastpickle.com 2016-05-28 20:24 GMT+01:00 Anuj Wadehra <[email protected]>: > Hi, > > We are using C* 2.0.x . What options are available if disk space is too > full to do compaction on huge sstables formed by STCS (created around long > ago but not getting compacted due to min_compaction_threshold being 4). > > We suspect that huge space will be released when 2 largest sstables get > compacted together such that tombstone eviction is possible. But there is > not enough space for compacting them together assuming that compaction > would need at least free disk=size of sstable1 + size of sstable 2 ?? > > I read STCS code and if no sstables are available for compactions, it > should pick individual sstable for compaction. But somehow, huge sstables > are not participating in individual compaction.. is it due to default 20% > tombstone threshold?? And if it so, forceUserdefinedcompaction or setting > unchecked_tombstone_compactions to true wont help either as tombstones are > less than 20% and not much disk would be recovered. > > It is not possible to add additional disks too. > > We see huge difference in disk utilization of different nodes. May be some > nodes were able to get away with tombstones while others didnt manage to > evict tombstones. > > > Would be good to know more alternatives from community. > > > Thanks > Anuj > > > > > > > > Sent from Yahoo Mail on Android > <https://overview.mail.yahoo.com/mobile/?.src=Android> >
