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Lars Hofhansl commented on HBASE-8369: -------------------------------------- I'll look forward to the flowers :) Thinking about this more, it is a good exercise to keep the M/R code out of HBase anyway to then see what we need to add to core HBase in order to allow for that. Hopefully that would enable other M/R usecases without any core patches needed. Note, though, that the only risky bits (if any) of this are exactly these hooks. Everything else is just additional classes. > MapReduce over snapshot files > ----------------------------- > > Key: HBASE-8369 > URL: https://issues.apache.org/jira/browse/HBASE-8369 > Project: HBase > Issue Type: New Feature > Components: mapreduce, snapshots > Reporter: Enis Soztutar > Assignee: Enis Soztutar > Fix For: 0.98.0 > > Attachments: HBASE-8369-0.94.patch, HBASE-8369-0.94_v2.patch, > HBASE-8369-0.94_v3.patch, HBASE-8369-0.94_v4.patch, HBASE-8369-0.94_v5.patch, > HBASE-8369-trunk_v1.patch, HBASE-8369-trunk_v2.patch, > HBASE-8369-trunk_v3.patch, hbase-8369_v0.patch, hbase-8369_v11.patch, > hbase-8369_v5.patch, hbase-8369_v6.patch, hbase-8369_v7.patch, > hbase-8369_v8.patch, hbase-8369_v9.patch > > > The idea is to add an InputFormat, which can run the mapreduce job over > snapshot files directly bypassing hbase server layer. The IF is similar in > usage to TableInputFormat, taking a Scan object from the user, but instead of > running from an online table, it runs from a table snapshot. We do one split > per region in the snapshot, and open an HRegion inside the RecordReader. A > RegionScanner is used internally for doing the scan without any HRegionServer > bits. > Users have been asking and searching for ways to run MR jobs by reading > directly from hfiles, so this allows new use cases if reading from stale data > is ok: > - Take snapshots periodically, and run MR jobs only on snapshots. > - Export snapshots to remote hdfs cluster, run the MR jobs at that cluster > without HBase cluster. > - (Future use case) Combine snapshot data with online hbase data: Scan from > yesterday's snapshot, but read today's data from online hbase cluster. -- This message was sent by Atlassian JIRA (v6.1.4#6159)