Gauge metrics are great for understanding the current state, but can somtimes hide problems
if there are many disconnect/reconnects.
This commit adds counter metrics for connections and streams to make it easier to see the
count of newly created connections and streams.
Instead of using retry.Run, which appears to have problems in some cases where it does not
emit an error message, use a for loop.
Increase the number of attempts and remove any sleep, since this operation is not that expensive to do
in a tight loop
Closing l.conns can lead to a race and a 'panic: send on closed chan' when a
connection is in the middle of being handled when the server is shutting down.
Found using '-race -count=800'
* Plumb Datacenter and Namespace to metrics provider in preparation for them being usable.
* Move metrics loader/status to a new component and show reason for being disabled.
* Remove stray console.log
* Rebuild AssetFS to resolve conflicts
* Yarn upgrade
* mend
Previously config entries sharing a kind & name but in different
namespaces could occasionally cause "stuck states" in replication
because the namespace fields were ignored during the differential
comparison phase.
Example:
Two config entries written to the primary:
kind=A,name=web,namespace=bar
kind=A,name=web,namespace=foo
Under the covers these both get saved to memdb, so they are sorted by
all 3 components (kind,name,namespace) during natural iteration. This
means that before the replication code does it's own incomplete sort,
the underlying data IS sorted by namespace ascending (bar comes before
foo).
After one pass of replication the primary and secondary datacenters have
the same set of config entries present. If
"kind=A,name=web,namespace=bar" were to be deleted, then things get
weird. Before replication the two sides look like:
primary: [
kind=A,name=web,namespace=foo
]
secondary: [
kind=A,name=web,namespace=bar
kind=A,name=web,namespace=foo
]
The differential comparison phase walks these two lists in sorted order
and first compares "kind=A,name=web,namespace=foo" vs
"kind=A,name=web,namespace=bar" and falsely determines they are the SAME
and are thus cause an update of "kind=A,name=web,namespace=foo". Then it
compares "<nothing>" with "kind=A,name=web,namespace=foo" and falsely
determines that the latter should be DELETED.
During reconciliation the deletes are processed before updates, and so
for a brief moment in the secondary "kind=A,name=web,namespace=foo" is
erroneously deleted and then immediately restored.
Unfortunately after this replication phase the final state is identical
to the initial state, so when it loops around again (rate limited) it
repeats the same set of operations indefinitely.
Required also converting some of the transaction functions to WriteTxn
because TxnRO() called the same helper as TxnRW.
This change allows us to return a memdb.Txn for read-only txn instead of
wrapping them with state.txn.
Prepopulate was setting entry.Expiry.HeapIndex to 0. Previously this would result in a call to heap.Fix(0)
which wasn't correct, but was also not really a problem because at worse it would re-notify.
With the recent change to extract cachettl it was changed to call Update(idx), which would have updated
the wrong entry.
A previous commit removed the setting of entry.Expiry so that the HeapIndex would be reported
as -1, and this commit adds a test and handles the -1 heap index.
Daniel Nephin
Kyle Havlovitz
hashicorp-ci
Paul Banks
R.B. Boyer
Freddy