From ffc55e9b15461c47f0fc38bb53495026bace10e8 Mon Sep 17 00:00:00 2001
From: tobi <31960611+tsmethurst@users.noreply.github.com>
Date: Mon, 20 Sep 2021 18:20:21 +0200
Subject: [PATCH] tweak db settings slightly (#238)

---
 internal/db/bundb/bundb.go | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/internal/db/bundb/bundb.go b/internal/db/bundb/bundb.go
index 400535da7..e1879f247 100644
--- a/internal/db/bundb/bundb.go
+++ b/internal/db/bundb/bundb.go
@@ -27,6 +27,7 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"runtime"
 	"strings"
 	"time"
 
@@ -116,6 +117,7 @@ func NewBunDBService(ctx context.Context, c *config.Config, log *logrus.Logger)
 			return nil, fmt.Errorf("could not create bundb postgres options: %s", err)
 		}
 		sqldb = stdlib.OpenDB(*opts)
+		tweakConnectionValues(sqldb)
 		conn = WrapDBConn(bun.NewDB(sqldb, pgdialect.New()), log)
 	case dbTypeSqlite:
 		// SQLITE
@@ -133,6 +135,7 @@ func NewBunDBService(ctx context.Context, c *config.Config, log *logrus.Logger)
 		if err != nil {
 			return nil, fmt.Errorf("could not open sqlite db: %s", err)
 		}
+		tweakConnectionValues(sqldb)
 		conn = WrapDBConn(bun.NewDB(sqldb, sqlitedialect.New()), log)
 
 		if c.DBConfig.Address == "file::memory:?cache=shared" {
@@ -319,10 +322,18 @@ func deriveBunDBPGOptions(c *config.Config) (*pgx.ConnConfig, error) {
 	cfg.TLSConfig = tlsConfig
 	cfg.Database = c.DBConfig.Database
 	cfg.PreferSimpleProtocol = true
+	cfg.RuntimeParams["application_name"] = c.ApplicationName
 
 	return cfg, nil
 }
 
+// https://bun.uptrace.dev/postgres/running-bun-in-production.html#database-sql
+func tweakConnectionValues(sqldb *sql.DB) {
+	maxOpenConns := 4 * runtime.GOMAXPROCS(0)
+	sqldb.SetMaxOpenConns(maxOpenConns)
+	sqldb.SetMaxIdleConns(maxOpenConns)
+}
+
 /*
 	CONVERSION FUNCTIONS
 */