Issue Summary

When verifying ingest tables on a leader, it is expected that the ingest table is empty and should not be dirty, allowing verification at all times. However, an unexpected EBUSY error was encountered in WT-16703 because the __statlog_server accesses the ingest table in parallel, contradicting this assumption.

Context

• The stat log server iterates over all open dhandles and accesses each of them, including ingest tables.
• Closing the ingest table dhandle may trigger the ingest dhandle sweep, potentially negating the advantages of creating ingest tables on the leader.
• Currently, ingest tables are closed only when the entire layered table is closed.
• There is a suggestion to introduce an intermediate state for ingest tables, indicating they are unused but not closed.
• Other components, such as the sweep server, may also access ingest tables and cause verify to return EBUSY.

Proposed Solution

• As a short-term resolution, avoid performing checks on ingest tables on the leader and leave a FIXME to investigate preventing all service threads on the leader from accessing ingest tables.
• In the stat log server, consider skipping ingest tables on the leader with logic such as:

  if leader and uri is ingest => skip file
  

• Investigate whether skipping ingest tables could be beneficial in other scenarios as well.
• Confirm the understanding of the ingest table dhandle lifecycle and explore options for intermediate states.