> also, if instead of files you think about handling blocks directly you can end up doing more stuff, like a proper compaction that require less I/O if N blocks are not changed, some crazy deduplication on tables with same content & similar...
Sounds like a step toward using a block pool directly and avoiding the filesystem layer (Hadoop 2+). On Fri, Mar 8, 2013 at 7:36 AM, Matteo Bertozzi <[email protected]>wrote: > sure having the hardlink support > (HDFS-3370<https://issues.apache.org/jira/browse/HDFS-3370>) > solve the HFileLink hack > but you still need to add extra metadata for splits (reference files) > > also, if instead of files you think about handling blocks directly > you can end up doing more stuff, like a proper compaction that > require less I/O if N blocks are not changed, some crazy deduplication > on tables with same content & similar... > > On Thu, Mar 7, 2013 at 11:22 PM, Sergey Shelukhin <[email protected] > >wrote: > > > Hmm... ranges sounds good, but for files, it would be nice if there were > a > > hardlink mechanism. > > It should be trivial to do in HDFS if blocks could belong to several > files. > > Then we don't have to have private cleanup code. > > > > On Thu, Mar 7, 2013 at 2:28 PM, Matteo Bertozzi <[email protected] > > >wrote: > > > > > This is seems to going in a super messy direction. > > > With HBASE-7806 the ideas was to cleanup all this crazy stuff > (HFileLink, > > > References, ...) > > > > > > unfortunately the initial decision of tight together the fs layout > > > and the tables/regions/families is bringing to all this workaround to > > have > > > something cool. > > > > > > If you put the files in one place, and the association in another you > > can > > > avoid all this complexity. > > > > > > /hbase/data/[file1, file 2, file 3, file N] > > > > > > table 1/region 1: [file 2] > > > table 1/region 2: [file 1 (from 0 to 50)] > > > table 1/region 3: [file 1 (from 50 to 100)] > > > table 2/region 1: [file 1, file 2] > > > > > > On Thu, Mar 7, 2013 at 10:13 PM, Stack <[email protected]> wrote: > > > > > > > Yes. That is a few trips to the NN listing directory contents and > then > > > > some edits/reading of .META. We would have to introduce a > QuarterHFile > > > to > > > > go with our HalfHFile (or rename HalfHFile as PieceO'HFile). > > > > > > > > > > > > St.Ack > > > > > > > > > > -- Best regards, - Andy Problems worthy of attack prove their worth by hitting back. - Piet Hein (via Tom White)
