Mike Percy has posted comments on this change. Change subject: design docs: Add tablet history GC design doc ......................................................................
Patch Set 4: (6 comments) http://gerrit.cloudera.org:8080/#/c/2853/4/docs/design-docs/tablet-history-gc.md File docs/design-docs/tablet-history-gc.md: PS4, Line 30: In the future > I'm fine in design docs, I just think it's weird to see in a user doc. I don't think it hurts in a design doc either. Leaving it unless I hear otherwise. Line 38: unlinks an open block that has become ancient history. > I think it's worth adding that Impala and Spark might have to run many scan Done Line 46: 1. The CompactRowSetsOp (merging compaction) tablet maintenance task. > a little paragraph of text on how this removes old deltas on output would b Done Line 47: 2. The UndoDeltaBlockGCOp tablet maintenance task. > worth describing this one somewhere (or a pointer to where it's described i Done PS4, Line 53: RowSets > DiskRowSets* Done PS4, Line 61: In cases where a merging tablet compaction is not run, we still want to remove : old rows. We could implement a maintenance task specifically for GCing old : rows. However, at the time of writing, this is not implemented because it : appears to be prone to causing write amplification. > think this could be clarified a little bit to contrast it to the UndoDeltaB Done -- To view, visit http://gerrit.cloudera.org:8080/2853 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: Ibd1776971ac4afa15a34daeced052913cf887dc3 Gerrit-PatchSet: 4 Gerrit-Project: kudu Gerrit-Branch: master Gerrit-Owner: Mike Percy <[email protected]> Gerrit-Reviewer: Adar Dembo <[email protected]> Gerrit-Reviewer: Dan Burkert <[email protected]> Gerrit-Reviewer: Jean-Daniel Cryans <[email protected]> Gerrit-Reviewer: Mike Percy <[email protected]> Gerrit-Reviewer: Todd Lipcon <[email protected]> Gerrit-HasComments: Yes
