NRG (2.11): Truncate entries without quorum from different pterm
#6027
Conversation
| @@ -3383,35 +3383,37 @@ func (n *raft) processAppendEntry(ae *appendEntry, sub *subscription) { | |||
| n.updateLeadChange(false) | |||
| } | |||
|
|
|||
| if (isNew && ae.pterm != n.pterm) || ae.pindex != n.pindex { | |||
There was a problem hiding this comment.
Removing isNew makes sure we can also detect differences if we're catching up, otherwise we could wrongly assume our own state is correct.
Specifically covered by the test TestNRGWALEntryWithoutQuorumMustTruncate/diverged
| @@ -3434,16 +3436,6 @@ func (n *raft) processAppendEntry(ae *appendEntry, sub *subscription) { | |||
| return | |||
| } | |||
|
|
|||
| // Check if only our terms do not match here. | |||
| if ae.pindex == n.pindex { | |||
There was a problem hiding this comment.
This condition could never be hit before, due to the condition above:
// Check if this is a lower or equal index than what we were expecting.
if ae.pindex <= n.pindex {Now moved up so the pterm can be corrected, otherwise we could spin.
Already covered by the test TestJetStreamClusterStreamCatchupNoState. Previously it used a different way to pass, likely truncating a bit too much and eventually converging. Now it only corrects the pterm as truncating is not needed.
There was a problem hiding this comment.
LGTM, have spoken to @MauriceVanVeen about some of the changes here and I think they're OK. Should be simpler than the previous approach of starting catchups at n.commit.
There was a problem hiding this comment.
I'm a little confused about some of these changes, but if you and Neil are confident, so am i.
It would be easier to review if each commit was atomic / self-contained and the commit message explained what the intent / reason was.
You have some comments in GH which is convenient, but if you look at this commit in a month will you find them?
Unlike GH comments, commit messages become part of history along with the change.
Signed-off-by: Maurice van Veen <[email protected]>
…mmitted Signed-off-by: Maurice van Veen <[email protected]>
Signed-off-by: Maurice van Veen <[email protected]>
MauriceVanVeen
force-pushed
the
maurice/simplify-truncate-entries-without-quorum
branch
from
df79a38
to
f9d2cc4
Compare
MauriceVanVeen
changed the title
pterm
|
@mprimi you good with this PR? |
|
@derekcollison yes, we reviewed this morning and i am onboard. |
derekcollison
deleted the
maurice/simplify-truncate-entries-without-quorum
branch
Reverts the changes made in #5987, but the tests are kept.
Instead opting for a simpler approach:
isNewcondition whenptermorpindexdon't match, to ensure consistency even during catchupae.pindex == n.pindexcondition up soptermcan be corrected (otherwise it would not be executed)Signed-off-by: Maurice van Veen [email protected]