proxysql

Commit Graph

Author	SHA1	Message	Date
Rene Cannao	a19894427e	Add independent DNS cache for PgSQL Fixes the watchdog asserts under DNS degradation reported in #5768. Symptom: with a PgSQL backend addressed by hostname, an unhealthy resolver made every PQconnectStart() block ~5s on getaddrinfo inside libpq. Under load, all PgSQL_Thread workers spent the bulk of each loop iteration in that synchronous DNS call, atomic_curtime fell behind the watchdog threshold (poll_timeout + 1s), and after restart_on_missing_heartbeats misses the watchdog asserts. MySQL avoids this because mysql-monitor's DNS cache lets MySQL_Connection::connect_start pass an IP directly to libmariadb; PgSQL had no equivalent. This change adds the equivalent for PgSQL, with state fully independent of the MySQL cache: * PgSQL_Monitor gains its own DNS_Cache, force_dns_cache_update flag, and dns_cache_{queried,lookup_success,record_updated} counters. PgSQL_Monitor::dns_lookup / update_dns_cache_from_pgsql_conn / trigger_dns_cache_update mirror the MySQL_Monitor surface. * A new background thread (PgSQL_monitor_dns_cache_pthread) drives PgSQL_Monitor::monitor_dns_cache(), which walks PgHGM->pgsql_servers_to_monitor and feeds the shared DNSResolverWorker pool. Launched alongside PgSQL_monitor_scheduler and lives independently of pgsql-monitor_enabled, matching MySQL. * PgSQL_Connection::connect_start now consults the cache. On a hit it appends `hostaddr=<ip>` to the libpq conninfo while keeping `host=<hostname>`; libpq documents this combo specifically to skip name resolution while preserving TLS hostname verification. On a miss / IP literal / disabled cache we fall back to the previous behavior (libpq does getaddrinfo). * Successful PgSQL connects seed the cache via update_dns_cache_from_pgsql_conn, so the second connect avoids getaddrinfo even before the resolver loop has visited the host. * The pgsql-monitor_local_dns_cache_ttl / _refresh_interval / _resolver_queue_maxsize variables (already accepted by Admin via PgSQL_Thread's variable registry) now actually propagate to pgsql_thread___monitor_local_dns_* globals. The propagation block in PgSQL_Thread::refresh_variables was previously commented out, so the values never reached anywhere. * The runtime stats output (SQL3_GlobalStatus) now exposes the PgSQL_Monitor_dns_cache_* counters alongside the existing PgSQL_Monitor_* counters. DNSResolverWorker is shared infrastructure added to DNS_Cache.hpp/cpp, used here by PgSQL_Monitor. MySQL_Monitor still uses its existing ConsumerThread-based pool; nothing about the MySQL cache changes.	1 month ago
Javier Jaramago Fernández	ba5af979ff	feat-wip: Add replication lag support for PostgreSQL monitoring	4 months ago
Rahim Kanji	fae283cf7e	Add SSL and non-SSL connection OK metrics for PostgreSQL monitor connections Adds two new metrics, ssl_connections_OK and non_ssl_connections_OK, to improve visibility into PostgreSQL monitor connection status.	7 months ago
Javier Jaramago Fernández	100630fba5	Second iteration on PostgreSQL monitoring POC This commit packs multiple fixes/improvements: - Added READONLY support for PostgreSQL. - Major rework for queries and statements used on monitoring checks: + Checks/Actions rewrote for single instance checks. + Reuse of prepared statements instance of re-preparation. - Fixed missing error handling in connection creation state machine. - Fixed connection rotation in connection pool (now FIFO). - Added support for configurable batching in scheduler thread, via '_interval_window' variables. These variables allows to define the burstiness of the scheduling within the processing interval. - Added new config variable 'pgsql-monitor_dbname'. Allows to control which 'db' will be target by monitoring connections. - Several fixes for 'poll' timeout computation for worker threads. - Fixed edge cases for current interval detection. - Reduced deviation in scheduling intervals computation. - Refactored and simplified connection event handling. - Improved error messages for monitoring actions. - Replaced several invalid uses of 'mysql_thread___monitor_' in favor or new 'mysql_thread___monitor_*' variables. - Honor '-M' argument for disabling monitoring support.	2 years ago
Javier Jaramago Fernández	705f50e0f9	Add initial POC for PostgreSQL monitoring support	2 years ago

5 Commits (a62d1b4e99d807fbf00ca3d022b65cf21902e098)