Adar Dembo has posted comments on this change. ( http://gerrit.cloudera.org:8080/12945 )
Change subject: tool: perf tablet_scan action ...................................................................... Patch Set 2: (3 comments) http://gerrit.cloudera.org:8080/#/c/12945/2/src/kudu/tools/tool_action_perf.cc File src/kudu/tools/tool_action_perf.cc: http://gerrit.cloudera.org:8080/#/c/12945/2/src/kudu/tools/tool_action_perf.cc@744 PS2, Line 744: FsManagerOpts()); > BTW can this tool be run on a currently-running tablet server? Is it read-o Nope; I think bootstrapping may rewrite WAL segments, the cmeta, the tmeta, or more stuff. Will double check and then add a comment. http://gerrit.cloudera.org:8080/#/c/12945/2/src/kudu/tools/tool_action_perf.cc@756 PS2, Line 756: if (FLAGS_use_hybrid_clock) { : clock.reset(new HybridClock()); : } else { : clock.reset(LogicalClock::CreateStartingAt(Timestamp::kInitialTimestamp)); : } > What does using the hybrid clock get us as far as scans are concerned? Coul I meant to follow-up on this. Without looking at the details, I thought perhaps some clock readings make their way into either in-memory state or into the rewritten WAL segments. If not, then always using a logical clock makes sense. Will check. http://gerrit.cloudera.org:8080/#/c/12945/2/src/kudu/tools/tool_action_perf.cc@869 PS2, Line 869: "Scan the contents of a local tablet" > nit: probably worth noting that this doesn't actually output the rows, othe OK. -- To view, visit http://gerrit.cloudera.org:8080/12945 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: kudu Gerrit-Branch: master Gerrit-MessageType: comment Gerrit-Change-Id: Id4667dcb2d9a21d77149ebdae2e29b7fce8b460b Gerrit-Change-Number: 12945 Gerrit-PatchSet: 2 Gerrit-Owner: Adar Dembo <[email protected]> Gerrit-Reviewer: Adar Dembo <[email protected]> Gerrit-Reviewer: Andrew Wong <[email protected]> Gerrit-Reviewer: Grant Henke <[email protected]> Gerrit-Reviewer: Mike Percy <[email protected]> Gerrit-Reviewer: Todd Lipcon <[email protected]> Gerrit-Comment-Date: Tue, 09 Apr 2019 19:23:49 +0000 Gerrit-HasComments: Yes
