Post-mortem: Postgres out of shared memory error
An investigation into PostgreSQL's memory error highlighted insights on transaction isolation and lock management. Increasing max_locks_per_transaction can resolve the "out of shared memory" issue, crucial for maintaining data consistency and preventing memory errors.
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A recent investigation into PostgreSQL's "out of shared memory" error revealed insights into transaction isolation and lock management. The error occurs when Postgres exhausts its lock memory capacity, determined by max_locks_per_transaction * (max_connections + max_prepared_transactions). Increasing max_locks_per_transaction can resolve this issue. Understanding transaction isolation levels, like Repeatable Read, is crucial as Postgres enforces isolation requirements to maintain data consistency. SIReadLocks are used to track accessed rows, impacting memory usage. Long-running non-READ ONLY transactions or orphaned transactions can lead to lock accumulation and memory saturation. Monitoring and addressing these issues, such as setting idle_in_transaction_session_timeout, can prevent memory errors and ensure database performance.
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Trealla Prolog is a compact interpreter written in C, compliant with ISO Prolog. It supports unbounded integers, UTF-8 atoms, efficient strings, and runs on Linux, Android, and WebAssembly. It offers C integration, SQLite access, concurrency features, and experimental functionalities. The project is open source under the MIT license.
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