When running a mongod test suite with featureFlagEnableSchemaEpochs enabled, we ran into the following two failures during validate:

Error 1: __wt_block_disagg_addr_unpack:171: Unsupported disaggregated address cookie version 5, min 1 (ENOTSUP) on file:index-e3c43215-….wt_stable
__schema_layered_stable_worker_verify:159: stable table verification failed on the leader

Error 2: __wt_block_disagg_addr_unpack:235: Disaggregated address cookie size mismatch: expected 0, got 28 (EINVAL)

Both failures likely indicate memory corruption. We didn't notice any checkpoint mismatch errors, so this is likely an indicative of a memory corruption.

It seems that the whole replica set shut down afterwards; we need to figure out if it did because other nodes encountered similar errors, or because the test shut it down due to the validation failure. If it's the former case, it would indicate that the corruption happened on the write path which would be a significantly more serious problem.

There is likewise no indication that this corruption was caused by being featureFlagEnableSchemaEpochs enabled; it could be just a coincidence that we run into this error in this specific test. But we should understand this issue more fully.

Raising this to P2, at least until we understand whether this error happened on the write path (which would be more serious) or if it was related to featureFlagEnableSchemaEpochs (in which case we can keep it disabled by default).