Adar Dembo has posted comments on this change. Change subject: design-docs: multi-master for 1.0 release ......................................................................
Patch Set 3: (3 comments) > For even more completeness, it'd be nice to have a list of the in-memory > caches and what feeds them. The information is scattered in the text at the > moment. I added some text, hopefully it helps. http://gerrit.cloudera.org:8080/#/c/2527/3/docs/design-docs/multi-master-1.0.md File docs/design-docs/multi-master-1.0.md: Line 183: (TBD) > At least on the Java side, the code that detects which master is the leader Good to know. I'm not in a position to flesh this out just yet, but I'll add that as a starting point. Line 230: when a tserver detects that there's a new leader > So they still need to "follow the leader"? No, this "detection" is done passively, via step #2 in "Heartbeat to all masters". I'll clarify that in the doc. Line 280: The tserver cache is expected to be warm very quickly as tservers are : now heartbeating to follower masters. > Because they already know to heartbeat to it and don't have to figure out t Sorry, what I wrote here was ambiguous. "Now" means "having implemented the changes described in Heartbeat to all masters", not "following a master failover". To rephrase, what I meant is that the tserver cache is expected to be warm one heartbeat interval after the master starts up. Given that, there's really no point in rebuilding it on metadata load. I'll make this more clear. > Also, should ex-leaders clear their caches? They could, but it doesn't matter either way because they're not supposed to receive any client requests or act on any TS heartbeats. I'll point this out. -- To view, visit http://gerrit.cloudera.org:8080/2527 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: Iad76012977a45370b72a04d608371cecf90442ef Gerrit-PatchSet: 3 Gerrit-Project: kudu Gerrit-Branch: master Gerrit-Owner: Adar Dembo <[email protected]> Gerrit-Reviewer: Adar Dembo <[email protected]> Gerrit-Reviewer: Dan Burkert <[email protected]> Gerrit-Reviewer: David Ribeiro Alves <[email protected]> Gerrit-Reviewer: Jean-Daniel Cryans Gerrit-Reviewer: Kudu Jenkins Gerrit-Reviewer: Mike Percy <[email protected]> Gerrit-Reviewer: Todd Lipcon <[email protected]> Gerrit-HasComments: Yes
