warnDBPoolUndersized emits a WARN log at startup when the active host count exceeds the configured DB connection pool limit by a meaningful margin. The default DB_CONNECTION_LIMIT (30) is fine for small deployments. Beyond ~50 hosts, synchronised report bursts can exhaust the pool and cause request
( ctx context.Context, cfg *config.Config, hostsStore *store.HostsStore, log *slog.Logger, )
| 94 | // count is not representative of any tenant's host count, and the per-tenant |
| 95 | // pools are sized independently of cfg.DBConnectionLimit on the primary. |
| 96 | func warnDBPoolUndersized( |
| 97 | ctx context.Context, |
| 98 | cfg *config.Config, |
| 99 | hostsStore *store.HostsStore, |
| 100 | log *slog.Logger, |
| 101 | ) { |
| 102 | if cfg.RegistryDatabaseURL != "" { |
| 103 | return // multi-host: per-tenant pool sizing is the wrong scope here |
| 104 | } |
| 105 | hosts, err := hostsStore.Count(ctx) |
| 106 | if err != nil { |
| 107 | return |
| 108 | } |
| 109 | if hosts <= dbPoolWarnHostThreshold { |
| 110 | return |
| 111 | } |
| 112 | recommended := recommendedDBPoolSize(hosts) |
| 113 | if cfg.DBConnectionLimit >= recommended { |
| 114 | return |
| 115 | } |
| 116 | log.Warn( |
| 117 | "database connection pool may be undersized for current host count", |
| 118 | "active_hosts", hosts, |
| 119 | "current_db_connection_limit", cfg.DBConnectionLimit, |
| 120 | "recommended_db_connection_limit", recommended, |
| 121 | "action", fmt.Sprintf( |
| 122 | "CONSIDER INCREASING DB_CONNECTION_LIMIT environment variable to %d (current: %d, active hosts: %d). With many hosts reporting concurrently, an undersized pool causes request queuing, retry backoff, and ultimately HTTP timeouts on agent reports.", |
| 123 | recommended, cfg.DBConnectionLimit, hosts, |
| 124 | ), |
| 125 | ) |
| 126 | } |
no test coverage detected