Module readback 

After the load: the committed offsets, and the read-back that the reconciler compares with the producers’ ledgers.

The read-back is a fresh consumer with no group, assigned every partition of a path and started from the earliest offset, that reads until it has reached each partition’s end. It runs once more only when the first pass found a record twice, to find every position of those records; holding a position for every record of a 72-hour run would cost more memory than the ledger it checks.

Functions

caught_up

Whether every partition of ends has a next offset at or past its end. A partition that ends at offset zero holds nothing and needs no read.

commit_checks

One CommitCheck per partition of acknowledged: the last commit the coordinator acknowledged before fault, against what OffsetFetch returns now and the partition’s log end.

groupless

A consumer with no group, for reading and for offset lookups.

partitions

Every partition of path.

read_back

What one reader saw of producer’s records on path.

round_trip

Produce one record to topic-partition with acks=all, then read it back at the offset it was acknowledged at, and return that offset.

stable

Whether no transaction is open on any partition: the last stable offset is the high watermark everywhere.

wait_stable

Wait until no transaction is open on path, so a read_committed read-back is not cut short by a transaction that its producer left open and the coordinator has yet to time out.