Identified a potential thread safety issue in __txn_global_query_timestamp. This function is designed to allow concurrent calls by multiple threads. However, it utilizes the default_session, which is not thread-safe. The concurrent use of a single session by multiple threads could lead to problems.

In our current setup, the connection API calls go through API_SESSION_INIT and WT_SINGLE_THREAD_CHECK_START, ensuring single-threaded access on the default session by taking a spinlock. This, however, is only enforced in diagnostic mode.

Scope:

• Reproduce the Issue
• Identify and Implement a Fix
• Evaluate the Need for conn->api_lock Lock