jon: I am planning on writing a custom compaction strategy. That's why the question is here, I figured the specifics of memtable -> sstable and cassandra internals are not a user question. If that still isn't deep enough for the dev thread, I will move all those questions to user.
On Wed, Feb 21, 2018 at 9:59 AM, Carl Mueller <carl.muel...@smartthings.com> wrote: > Thank you all! > > On Tue, Feb 20, 2018 at 7:35 PM, kurt greaves <k...@instaclustr.com> > wrote: > >> Probably a lot of work but it would be incredibly useful for vnodes if >> flushing was range aware (to be used with RangeAwareCompactionStrategy). >> The writers are already range aware for JBOD, but that's not terribly >> valuable ATM. >> >> On 20 February 2018 at 21:57, Jeff Jirsa <jji...@gmail.com> wrote: >> >>> There are some arguments to be made that the flush should consider >>> compaction strategy - would allow a bug flush to respect LCS filesizes or >>> break into smaller pieces to try to minimize range overlaps going from l0 >>> into l1, for example. >>> >>> I have no idea how much work would be involved, but may be worthwhile. >>> >>> >>> -- >>> Jeff Jirsa >>> >>> >>> On Feb 20, 2018, at 1:26 PM, Jon Haddad <j...@jonhaddad.com> wrote: >>> >>> The file format is independent from compaction. A compaction strategy >>> only selects sstables to be compacted, that’s it’s only job. It could have >>> side effects, like generating other files, but any decent compaction >>> strategy will account for the fact that those other files don’t exist. >>> >>> I wrote a blog post a few months ago going over some of the nuance of >>> compaction you mind find informative: http://thelastpic >>> kle.com/blog/2017/03/16/compaction-nuance.html >>> >>> This is also the wrong mailing list, please direct future user questions >>> to the user list. The dev list is for development of Cassandra itself. >>> >>> Jon >>> >>> On Feb 20, 2018, at 1:10 PM, Carl Mueller <carl.muel...@smartthings.com> >>> wrote: >>> >>> When memtables/CommitLogs are flushed to disk/sstable, does the sstable >>> go >>> through sstable organization specific to each compaction strategy, or is >>> the sstable creation the same for all compactionstrats and it is up to >>> the >>> compaction strategy to recompact the sstable if desired? >>> >>> >>> >> >
