Mike Percy has posted comments on this change. Change subject: KUDU-1506 Add consensus lag metrics ......................................................................
Patch Set 3: (4 comments) I haven't been following this but I was just curious and thought I'd take a look. I have some high level questions though: 1. I am having trouble deciding whether these metrics are meant to have meaning on nodes other than the leader. I think yes. 2. I am not sure what this lag metric means exactly. It seems like it means means highest index that the leader knows about or highest index the current node has ever seen. http://gerrit.cloudera.org:8080/#/c/6451/3/src/kudu/consensus/consensus.proto File src/kudu/consensus/consensus.proto: PS3, Line 358: any peer in the config Just looking at the .proto file, it's hard for me to understand what this means. Let's make this more precise by saying something like "if this node is the leader, this is the highest index that this leader has replicated to at least one other machine." ... I am guessing that is what it means? http://gerrit.cloudera.org:8080/#/c/6451/3/src/kudu/consensus/consensus_queue.cc File src/kudu/consensus/consensus_queue.cc: PS3, Line 106: max How about calling this 'latest' instead of 'max'? Here and elsewhere. When I think maximum OpId I think `MakeOpId(INT64_MAX, INT64_MAX)`. PS3, Line 157: queue_state_.max_replicated_index = committed_index Hmm, can't we get a more accurate / tighter bound than this? http://gerrit.cloudera.org:8080/#/c/6451/3/src/kudu/consensus/consensus_queue.h File src/kudu/consensus/consensus_queue.h: PS3, Line 338: max_replicated_index Shouldn't this be bounded by queue_state_.last_appended? Is not, is that a bug? -- To view, visit http://gerrit.cloudera.org:8080/6451 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: Ida8e992cc2397ca8d5873e62961a65f618d52c36 Gerrit-PatchSet: 3 Gerrit-Project: kudu Gerrit-Branch: master Gerrit-Owner: Andrew Wong <aw...@cloudera.com> Gerrit-Reviewer: Andrew Wong <aw...@cloudera.com> Gerrit-Reviewer: David Ribeiro Alves <dral...@apache.org> Gerrit-Reviewer: Kudu Jenkins Gerrit-Reviewer: Mike Percy <mpe...@apache.org> Gerrit-Reviewer: Todd Lipcon <t...@apache.org> Gerrit-HasComments: Yes
