Timer of the append_batch operation on the kafka logstore.
This timer only measures the duration of the read operation, not measures the total duration of replay.
Counter of conditional creates of the object store logstore that
succeeded, an identical retry that found its own object included. A
create that failed is counted in the create failure or conflict counter
instead.
Counter of conditional creates of the object store logstore that found
an object with different content. In the durable mode an object of an
earlier epoch fails the batch like a transient failure; any other
conflict poisons the store.
Counter of conditional creates of the object store logstore the object
store did not confirm, which fail the appends behind them in the
durable mode and are repeated in the enqueued mode.
Number of object store logstores in the enqueued mode whose backlog
the object store refuses with an error that repeating the create
cannot settle, such as denied access or a missing bucket. Such a store
keeps its backlog, attempts it again with backoff and rejects appends
until a create succeeds.
Counter of regions the object store logstore let open although its
prefix does not hold their WAL history, because
accept_missing_history is set; their writes that were not flushed
are lost.
How long a read stream of the object store logstore took to serve the
replay of one region, recorded once the stream has been read to its
end; one that fails or is dropped part way records nothing.
Counter of objects a recovery of the object store logstore that
succeeded read footers from, which is what its time is spent on. It
counts the objects of the same recoveries the timer above measures, so
an abandoned one contributes to neither.
How long a recovery of the object store logstore that succeeded took to
rebuild its catalog, which is the part of a restart the WAL is
responsible for. A recovery that was abandoned records nothing.
Counter of appends the object store logstore rejected while its
backlog is refused, see the gauge above. They take no entry id and
fail with a retryable error. Releases of dropped regions failed in
that state count too; their records wait for the next object.
How long an object of the object store logstore takes to become durable
once its batch is sealed, sampled for every conditional create that
succeeds, an identical retry included. The time runs from the seal, so
it includes any wait for a create slot and, in the enqueued mode,
every repeated attempt and the delay before it.
Counter of appends the object store logstore held back until an upload
completed: in either mode because the sealed batches waiting to become
durable left no room for another, and in the enqueued mode also
because the unpersisted backlog reached a threshold. Either says the
write rate is above what the uploads sustain.
How long such an append stays held back, until it is admitted or until
it is refused, a stop, a terminal error or the teardown of the store
releasing it included, which is the latency the enqueued mode pays
once the backlog is at a threshold.
Timer of the append_batch operation on the raft-engine logstore.
This timer only measures the duration of the read operation, not measures the total duration of replay.