Pop stops working when under high load

[paganotoni]

Description

If on your database.yml you specify a pool: count that is minor than the number of requests you will be receiving, at some point all database related operations are nor performed while in buffalo the rest of handlers/middlewares (which are not related with database connection) keep working .

Steps to Reproduce the Problem

1. Create a coke app with buffalo g new coke --force
2. Generate a resource buffalo g resource people
3. Run migrations and change your actions/flavours.go file List action to look like:

// List gets all People. This function is mapped to the path
// GET /people
func (v PeopleResource) List(c buffalo.Context) error {
	// Get the DB connection from the context
	tx, ok := c.Value("tx").(*pop.Connection)

	models.DB.Create(&models.Person{})

	if !ok {
		return errors.WithStack(errors.New("no transaction found"))
	}

	people := &models.People{}

	// Paginate results. Params "page" and "per_page" control pagination.
	// Default values are "page=1" and "per_page=20".
	q := tx.PaginateFromParams(c.Params())

	// Retrieve all People from the DB
	if err := q.All(people); err != nil {
		return errors.WithStack(err)
	}

	// Add the paginator to the context so it can be used in the template.
	c.Set("pagination", q.Paginator)

	return c.Render(200, r.Auto(c, people))
}

Notice that we use models.DB instead of the tx variable to do the insert. If instead i do tx.Create it works very well.

Expected Behavior

If something goes wrong pop/buffalo should say something about it.

Actual Behavior

Pop doesn't say anything and app freezes any database operation.

Info

Buffalo Version

v0.14.1

App Information

Pwd=/Users/paganotoni/go/src/github.com/paganotoni/coke Root=/Users/paganotoni/go/src/github.com/paganotoni/coke GoPath=/Users/paganotoni/go PackagePkg=github.com/paganotoni/coke ActionsPkg=github.com/paganotoni/coke/actions ModelsPkg=github.com/paganotoni/coke/models GriftsPkg=github.com/paganotoni/coke/grifts WithModules=true Name=coke Bin=bin/coke VCS=git WithPop=true WithSQLite=false WithDep=false WithWebpack=true WithNodeJs=true WithYarn=true WithDocker=true WithGrifts=true AsWeb=true AsAPI=false PackageJSON={map[]}

Go Version

go version go1.12.1 darwin/amd64

Go Env

GOARCH="amd64" GOBIN="" GOCACHE="/Users/paganotoni/Library/Caches/go-build" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="darwin" GOOS="darwin" GOPATH="/Users/paganotoni/go" GOPROXY="http://athens.wawand.co" GORACE="" GOROOT="/usr/local/Cellar/go/1.12.1/libexec" GOTMPDIR="" GOTOOLDIR="/usr/local/Cellar/go/1.12.1/libexec/pkg/tool/darwin_amd64" GCCGO="gccgo" CC="clang" CXX="clang++" CGO_ENABLED="1" GOMOD="/Users/paganotoni/go/src/github.com/paganotoni/coke/go.mod" CGO_CFLAGS="-g -O2" CGO_CPPFLAGS="" CGO_CXXFLAGS="-g -O2" CGO_FFLAGS="-g -O2" CGO_LDFLAGS="-g -O2" PKG_CONFIG="pkg-config" GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/gg/jnd1lf7s6zx38rcybmddnw3h0000gn/T/go-build953300490=/tmp/go-build -gno-record-gcc-switches -fno-common"

Node Version

v11.9.0

NPM Version

6.8.0

Yarn Version

1.12.3

PostgreSQL Version

pg_ctl (PostgreSQL) 11.2

MySQL Version

MySQL Not Found

SQLite Version

3.24.0 2018-06-04 14:10:15 95fbac39baaab1c3a84fdfc82ccb7f42398b2e92f18a2a57bce1d4a713cbaapl

Dep Version

could not find a Gopkg.toml file

Dep Status

could not find a Gopkg.toml file

config/buffalo-app.toml

name = "coke" bin = "bin/coke" vcs = "git" with_pop = true with_sqlite = false with_dep = false with_webpack = true with_nodejs = true with_yarn = true with_docker = true with_grifts = true as_web = true as_api = false

config/buffalo-plugins.toml

[[plugin]] binary = "buffalo-plugins" go_get = "github.com/gobuffalo/buffalo-plugins"

[[plugin]] binary = "buffalo-pop" go_get = "github.com/gobuffalo/buffalo-pop"

go.mod

module github.com/paganotoni/coke

go 1.12

require ( github.com/gobuffalo/buffalo v0.14.2 github.com/gobuffalo/buffalo-pop v1.9.0 github.com/gobuffalo/envy v1.6.15 github.com/gobuffalo/mw-csrf v0.0.0-20190129204204-25460a055517 github.com/gobuffalo/mw-forcessl v0.0.0-20180802152810-73921ae7a130 github.com/gobuffalo/mw-i18n v0.0.0-20190129204410-552713a3ebb4 github.com/gobuffalo/mw-paramlogger v0.0.0-20190224201358-0d45762ab655 github.com/gobuffalo/packr/v2 v2.0.6 github.com/gobuffalo/pop v4.10.0+incompatible github.com/gobuffalo/validate v2.0.3+incompatible github.com/gofrs/uuid v3.2.0+incompatible github.com/jackc/pgx v3.3.0+incompatible // indirect github.com/markbates/going v1.0.3 // indirect github.com/pkg/errors v0.8.1 github.com/spf13/afero v1.2.1 // indirect github.com/unrolled/secure v1.0.0 )