Gorm with postgres taking too long on first sql

I'm using Gorm with postgres driver. I'm testing some queries and realize the first query will always be very slow (100ms +). I've tested the same benchmark in MySQL, and that not occurs.

package main

import (
	"fmt"
	"os"
	"strings"
	"time"

	"gorm.io/driver/mysql"
	"gorm.io/driver/postgres"
	"gorm.io/gorm"
)

var config = gorm.Config{
	PrepareStmt:            true,
	SkipDefaultTransaction: true,
}

func main() {
	dsn := "postgresql://postgres:senha123@localhost:5432/postgres?sslmode=disable"

	start := time.Now()
	db, err := gorm.Open(postgres.Open(dsn), &config)
	if err != nil {
		panic("failed to connect database")
	}

	fmt.Printf("==> Open connection: %s\n", time.Since(start))
	executeBenchmark(db)
}

func executeBenchmark(db *gorm.DB) {
	user := &User{
		Name:     "Inserted",
		Email:    "m@m.com",
		Password: "asdf",
	}

	// Test Create performance
	start := time.Now()
	db.Create(&user)
	fmt.Printf("==> Create user: %s\n", time.Since(start))

	// Test Select by email performance
	start = time.Now()
	db.Where(&User{Email: user.Email}).First(&user)
	fmt.Printf("==> Select by EMAIL user: %s\n", time.Since(start))

	// Test Update performance
	start = time.Now()
	db.Model(&user).Where(&User{ID: user.ID}).Update("name", "updated")
	fmt.Printf("==> Update user: %s\n", time.Since(start))

	// Test delete performance
	start = time.Now()
	db.Unscoped().Delete(&User{}, user.ID)
	fmt.Printf("==> Delete User user: %s\n", time.Since(start))
}

Postgres result:

==> Open connection: 3.1902ms
==> Create user: 122.5041ms
==> Select by EMAIL user: 2.3431ms
==> Update user: 2.7019ms
==> Delete User user: 1.1994ms

If I execute the Select by EMAIL user first, it will be the slow query instead...

Running the same benchmark with MySQL:

==> Open connection: 6.2952ms
==> Create user: 8.98ms
==> Select by EMAIL user: 1.3064ms
==> Update user: 3.6067ms
==> Delete User user: 3.0996ms

Go: 1.20 <br />
gorm: 1.25.0 <br />
driver postgres: 1.5.0 <br />
driver MySQL: 1.5.0 <br />

I want to understand why the first query always takes 100ms+ and how I can improve it. Please, help =)

I still don't know why this is happening, but I ran this benchmark inside a docker container using the same db network and I got better results:

==> Open connection: 336.317µs
==> Create user: 7.741506ms
==> Select by EMAIL user: 999.892µs
==> Update user: 1.034811ms
==> Delete User user: 912.888µs

The first SQL is still the worst, but I think it is fine. I'll assume that the problem was something in my localhost with docker...