open-nomad/client/fingerprint/env_aws_test.go
Seth Hoenig f8596a3602 env_aws: use best-effort lookup table for CPU performance in EC2
Fixes #7681

The current behavior of the CPU fingerprinter in AWS is that it
reads the **current** speed from `/proc/cpuinfo` (`CPU MHz` field).

This is because the max CPU frequency is not available by reading
anything on the EC2 instance itself. Normally on Linux one would
look at e.g. `sys/devices/system/cpu/cpuN/cpufreq/cpuinfo_max_freq`
or perhaps parse the values from the `CPU max MHz` field in
`/proc/cpuinfo`, but those values are not available.

Furthermore, no metadata about the CPU is made available in the
EC2 metadata service.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instancedata-data-categories.html

Since `go-psutil` cannot determine the max CPU speed it defaults to
the current CPU speed, which could be basically any number between
0 and the true max. This is particularly bad on large, powerful
reserved instances which often idle at ~800 MHz while Nomad does
its fingerprinting (typically IO bound), which Nomad then uses as
the max, which results in severe loss of available resources.

Since the CPU specification is unavailable programmatically (at least
not without sudo) use a best-effort lookup table. This table was
generated by going through every instance type in AWS documentation
and copy-pasting the numbers.
https://aws.amazon.com/ec2/instance-types/

This approach obviously is not ideal as future instance types will
need to be added as they are introduced to AWS. However, using the
table should only be an improvement over the status quo since right
now Nomad miscalculates available CPU resources on all instance types.
2020-04-28 19:01:33 -06:00

449 lines
13 KiB
Go

package fingerprint
import (
"fmt"
"net/http"
"net/http/httptest"
"testing"
"github.com/hashicorp/nomad/client/config"
"github.com/hashicorp/nomad/helper/testlog"
"github.com/hashicorp/nomad/nomad/structs"
"github.com/stretchr/testify/require"
)
func TestEnvAWSFingerprint_nonAws(t *testing.T) {
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = "http://127.0.0.1/latest"
node := &structs.Node{
Attributes: make(map[string]string),
}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.Empty(t, response.Attributes)
}
func TestEnvAWSFingerprint_aws(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, awsStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{
Attributes: make(map[string]string),
}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
keys := []string{
"platform.aws.ami-id",
"unique.platform.aws.hostname",
"unique.platform.aws.instance-id",
"platform.aws.instance-type",
"unique.platform.aws.local-hostname",
"unique.platform.aws.local-ipv4",
"unique.platform.aws.public-hostname",
"unique.platform.aws.public-ipv4",
"platform.aws.placement.availability-zone",
"unique.network.ip-address",
}
for _, k := range keys {
assertNodeAttributeContains(t, response.Attributes, k)
}
require.NotEmpty(t, response.Links)
// confirm we have at least instance-id and ami-id
for _, k := range []string{"aws.ec2"} {
assertNodeLinksContains(t, response.Links, k)
}
}
func TestNetworkFingerprint_AWS(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, awsStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{
Attributes: make(map[string]string),
}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
assertNodeAttributeContains(t, response.Attributes, "unique.network.ip-address")
require.NotNil(t, response.NodeResources)
require.Len(t, response.NodeResources.Networks, 1)
// Test at least the first Network Resource
net := response.NodeResources.Networks[0]
require.NotEmpty(t, net.IP, "Expected Network Resource to have an IP")
require.NotEmpty(t, net.CIDR, "Expected Network Resource to have a CIDR")
require.NotEmpty(t, net.Device, "Expected Network Resource to have a Device Name")
}
func TestNetworkFingerprint_AWS_network(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, awsStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
{
node := &structs.Node{
Attributes: make(map[string]string),
}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.True(t, response.Detected, "expected response to be applicable")
assertNodeAttributeContains(t, response.Attributes, "unique.network.ip-address")
require.NotNil(t, response.NodeResources)
require.Len(t, response.NodeResources.Networks, 1)
// Test at least the first Network Resource
net := response.NodeResources.Networks[0]
require.NotEmpty(t, net.IP, "Expected Network Resource to have an IP")
require.NotEmpty(t, net.CIDR, "Expected Network Resource to have a CIDR")
require.NotEmpty(t, net.Device, "Expected Network Resource to have a Device Name")
require.Equal(t, 1000, net.MBits)
}
// Try again this time setting a network speed in the config
{
node := &structs.Node{
Attributes: make(map[string]string),
}
cfg := &config.Config{
NetworkSpeed: 10,
}
request := &FingerprintRequest{Config: cfg, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
assertNodeAttributeContains(t, response.Attributes, "unique.network.ip-address")
require.NotNil(t, response.NodeResources)
require.Len(t, response.NodeResources.Networks, 1)
// Test at least the first Network Resource
net := response.NodeResources.Networks[0]
require.NotEmpty(t, net.IP, "Expected Network Resource to have an IP")
require.NotEmpty(t, net.CIDR, "Expected Network Resource to have a CIDR")
require.NotEmpty(t, net.Device, "Expected Network Resource to have a Device Name")
require.Equal(t, 10, net.MBits)
}
}
func TestNetworkFingerprint_AWS_NoNetwork(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, noNetworkAWSStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{
Attributes: make(map[string]string),
}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.True(t, response.Detected, "expected response to be applicable")
require.Equal(t, "ami-1234", response.Attributes["platform.aws.ami-id"])
require.Nil(t, response.NodeResources)
}
func TestNetworkFingerprint_AWS_IncompleteImitation(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, incompleteAWSImitationStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{
Attributes: make(map[string]string),
}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.False(t, response.Detected, "expected response not to be applicable")
require.NotContains(t, response.Attributes, "platform.aws.ami-id")
require.Nil(t, response.NodeResources)
}
func TestCPUFingerprint_AWS_InstanceFound(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, awsStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{Attributes: make(map[string]string)}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.True(t, response.Detected)
require.Equal(t, "2.5 GHz AMD EPYC 7000 series", response.Attributes["cpu.modelname"])
require.Equal(t, "2500", response.Attributes["cpu.frequency"])
require.Equal(t, "8", response.Attributes["cpu.numcores"])
require.Equal(t, "20000", response.Attributes["cpu.totalcompute"])
require.Equal(t, 20000, response.Resources.CPU)
require.Equal(t, int64(20000), response.NodeResources.Cpu.CpuShares)
}
func TestCPUFingerprint_AWS_OverrideCompute(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, awsStubs)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{Attributes: make(map[string]string)}
request := &FingerprintRequest{Config: &config.Config{
CpuCompute: 99999,
}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.True(t, response.Detected)
require.Equal(t, "2.5 GHz AMD EPYC 7000 series", response.Attributes["cpu.modelname"])
require.Equal(t, "2500", response.Attributes["cpu.frequency"])
require.Equal(t, "8", response.Attributes["cpu.numcores"])
require.NotContains(t, response.Attributes, "cpu.totalcompute")
require.Nil(t, response.Resources) // defaults in cpu fingerprinter
require.Zero(t, response.NodeResources.Cpu) // defaults in cpu fingerprinter
}
func TestCPUFingerprint_AWS_InstanceNotFound(t *testing.T) {
endpoint, cleanup := startFakeEC2Metadata(t, unknownInstanceType)
defer cleanup()
f := NewEnvAWSFingerprint(testlog.HCLogger(t))
f.(*EnvAWSFingerprint).endpoint = endpoint
node := &structs.Node{Attributes: make(map[string]string)}
request := &FingerprintRequest{Config: &config.Config{}, Node: node}
var response FingerprintResponse
err := f.Fingerprint(request, &response)
require.NoError(t, err)
require.True(t, response.Detected)
require.NotContains(t, response.Attributes, "cpu.modelname")
require.NotContains(t, response.Attributes, "cpu.frequency")
require.NotContains(t, response.Attributes, "cpu.numcores")
require.NotContains(t, response.Attributes, "cpu.totalcompute")
require.Nil(t, response.Resources)
require.Nil(t, response.NodeResources)
}
/// Utility functions for tests
func startFakeEC2Metadata(t *testing.T, endpoints []endpoint) (endpoint string, cleanup func()) {
ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
for _, e := range endpoints {
if r.RequestURI == e.Uri {
w.Header().Set("Content-Type", e.ContentType)
fmt.Fprintln(w, e.Body)
}
}
}))
return ts.URL + "/latest", ts.Close
}
type routes struct {
Endpoints []*endpoint `json:"endpoints"`
}
type endpoint struct {
Uri string `json:"uri"`
ContentType string `json:"content-type"`
Body string `json:"body"`
}
// awsStubs mimics normal EC2 instance metadata
var awsStubs = []endpoint{
{
Uri: "/latest/meta-data/ami-id",
ContentType: "text/plain",
Body: "ami-1234",
},
{
Uri: "/latest/meta-data/hostname",
ContentType: "text/plain",
Body: "ip-10-0-0-207.us-west-2.compute.internal",
},
{
Uri: "/latest/meta-data/placement/availability-zone",
ContentType: "text/plain",
Body: "us-west-2a",
},
{
Uri: "/latest/meta-data/instance-id",
ContentType: "text/plain",
Body: "i-b3ba3875",
},
{
Uri: "/latest/meta-data/instance-type",
ContentType: "text/plain",
Body: "t3a.2xlarge",
},
{
Uri: "/latest/meta-data/local-hostname",
ContentType: "text/plain",
Body: "ip-10-0-0-207.us-west-2.compute.internal",
},
{
Uri: "/latest/meta-data/local-ipv4",
ContentType: "text/plain",
Body: "10.0.0.207",
},
{
Uri: "/latest/meta-data/public-hostname",
ContentType: "text/plain",
Body: "ec2-54-191-117-175.us-west-2.compute.amazonaws.com",
},
{
Uri: "/latest/meta-data/public-ipv4",
ContentType: "text/plain",
Body: "54.191.117.175",
},
}
var unknownInstanceType = []endpoint{
{
Uri: "/latest/meta-data/ami-id",
ContentType: "text/plain",
Body: "ami-1234",
},
{
Uri: "/latest/meta-data/hostname",
ContentType: "text/plain",
Body: "ip-10-0-0-207.us-west-2.compute.internal",
},
{
Uri: "/latest/meta-data/placement/availability-zone",
ContentType: "text/plain",
Body: "us-west-2a",
},
{
Uri: "/latest/meta-data/instance-id",
ContentType: "text/plain",
Body: "i-b3ba3875",
},
{
Uri: "/latest/meta-data/instance-type",
ContentType: "text/plain",
Body: "xyz123.uber",
},
}
// noNetworkAWSStubs mimics an EC2 instance but without local ip address
// may happen in environments with odd EC2 Metadata emulation
var noNetworkAWSStubs = []endpoint{
{
Uri: "/latest/meta-data/ami-id",
ContentType: "text/plain",
Body: "ami-1234",
},
{
Uri: "/latest/meta-data/hostname",
ContentType: "text/plain",
Body: "ip-10-0-0-207.us-west-2.compute.internal",
},
{
Uri: "/latest/meta-data/placement/availability-zone",
ContentType: "text/plain",
Body: "us-west-2a",
},
{
Uri: "/latest/meta-data/instance-id",
ContentType: "text/plain",
Body: "i-b3ba3875",
},
{
Uri: "/latest/meta-data/instance-type",
ContentType: "text/plain",
Body: "m3.2xlarge",
},
{
Uri: "/latest/meta-data/local-hostname",
ContentType: "text/plain",
Body: "ip-10-0-0-207.us-west-2.compute.internal",
},
{
Uri: "/latest/meta-data/local-ipv4",
ContentType: "text/plain",
Body: "",
},
{
Uri: "/latest/meta-data/public-hostname",
ContentType: "text/plain",
Body: "ec2-54-191-117-175.us-west-2.compute.amazonaws.com",
},
{
Uri: "/latest/meta-data/public-ipv4",
ContentType: "text/plain",
Body: "54.191.117.175",
},
}
// incompleteAWSImitationsStub mimics environments where some AWS endpoints
// return empty, namely Hetzner
var incompleteAWSImitationStubs = []endpoint{
{
Uri: "/latest/meta-data/hostname",
ContentType: "text/plain",
Body: "ip-10-0-0-207.us-west-2.compute.internal",
},
{
Uri: "/latest/meta-data/instance-id",
ContentType: "text/plain",
Body: "i-b3ba3875",
},
{
Uri: "/latest/meta-data/local-ipv4",
ContentType: "text/plain",
Body: "",
},
{
Uri: "/latest/meta-data/public-ipv4",
ContentType: "text/plain",
Body: "54.191.117.175",
},
}