Files
coder/cli/exp_scaletest_dynamicparameters.go
T
Spike Curtis 73253df6bf fix: use separate HTTP clients in scale test load generators (#21288)
While scale testing, I noticed that our load generators send basically
all requests to a single Coderd instance.

e.g. 


![image.png](https://app.graphite.com/user-attachments/assets/e259862a-adf1-47e7-a37b-fd14e420058e.png)


This is because our scale test commands create all `Runner`s using the
same codersdk Client, which means they share an underlying HTTP client.
With HTTP/2 a single TCP session can multiplex many different HTTP
requests (including websockets). So, it creates a single TCP connection
to a single coderd, and then sends all the requests down the one TCP
connections.

This PR modifies the `exp scaletest` load generator commands to create
an independent HTTP client per `Runner`. This means that each runner
will create its own TCP connection. This should help spread the load and
make a more realistic test, because in a real deployment, scaled out
load will be coming over different TCP connections.
2025-12-19 12:22:49 +04:00

179 lines
5.5 KiB
Go

//go:build !slim
package cli
import (
"fmt"
"time"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
"golang.org/x/xerrors"
"github.com/coder/coder/v2/scaletest/loadtestutil"
"cdr.dev/slog"
"cdr.dev/slog/sloggers/sloghuman"
"github.com/coder/serpent"
"github.com/coder/coder/v2/scaletest/dynamicparameters"
"github.com/coder/coder/v2/scaletest/harness"
)
const (
dynamicParametersTestName = "dynamic-parameters"
)
func (r *RootCmd) scaletestDynamicParameters() *serpent.Command {
var (
templateName string
provisionerTags []string
numEvals int64
tracingFlags = &scaletestTracingFlags{}
prometheusFlags = &scaletestPrometheusFlags{}
// This test requires unlimited concurrency
timeoutStrategy = &timeoutFlags{}
)
orgContext := NewOrganizationContext()
output := &scaletestOutputFlags{}
cmd := &serpent.Command{
Use: "dynamic-parameters",
Short: "Generates load on the Coder server evaluating dynamic parameters",
Long: `It is recommended that all rate limits are disabled on the server before running this scaletest. This test generates many login events which will be rate limited against the (most likely single) IP.`,
Handler: func(inv *serpent.Invocation) error {
ctx := inv.Context()
outputs, err := output.parse()
if err != nil {
return xerrors.Errorf("could not parse --output flags")
}
client, err := r.InitClient(inv)
if err != nil {
return err
}
if templateName == "" {
return xerrors.Errorf("template cannot be empty")
}
tags, err := ParseProvisionerTags(provisionerTags)
if err != nil {
return err
}
org, err := orgContext.Selected(inv, client)
if err != nil {
return err
}
_, err = requireAdmin(ctx, client)
if err != nil {
return err
}
reg := prometheus.NewRegistry()
metrics := dynamicparameters.NewMetrics(reg, "concurrent_evaluations")
logger := slog.Make(sloghuman.Sink(inv.Stdout)).Leveled(slog.LevelDebug)
prometheusSrvClose := ServeHandler(ctx, logger, promhttp.HandlerFor(reg, promhttp.HandlerOpts{}), prometheusFlags.Address, "prometheus")
defer prometheusSrvClose()
tracerProvider, closeTracing, tracingEnabled, err := tracingFlags.provider(ctx)
if err != nil {
return xerrors.Errorf("create tracer provider: %w", err)
}
defer func() {
// Allow time for traces to flush even if command context is
// canceled. This is a no-op if tracing is not enabled.
_, _ = fmt.Fprintln(inv.Stderr, "\nUploading traces...")
if err := closeTracing(ctx); err != nil {
_, _ = fmt.Fprintf(inv.Stderr, "\nError uploading traces: %+v\n", err)
}
// Wait for prometheus metrics to be scraped
_, _ = fmt.Fprintf(inv.Stderr, "Waiting %s for prometheus metrics to be scraped\n", prometheusFlags.Wait)
<-time.After(prometheusFlags.Wait)
}()
tracer := tracerProvider.Tracer(scaletestTracerName)
partitions, err := dynamicparameters.SetupPartitions(ctx, client, org.ID, templateName, tags, numEvals, logger)
if err != nil {
return xerrors.Errorf("setup dynamic parameters partitions: %w", err)
}
th := harness.NewTestHarness(
timeoutStrategy.wrapStrategy(harness.ConcurrentExecutionStrategy{}),
// there is no cleanup since it's just a connection that we sever.
nil)
for i, part := range partitions {
for j := range part.ConcurrentEvaluations {
cfg := dynamicparameters.Config{
TemplateVersion: part.TemplateVersion.ID,
Metrics: metrics,
MetricLabelValues: []string{fmt.Sprintf("%d", part.ConcurrentEvaluations)},
}
// use an independent client for each Runner, so they don't reuse TCP connections. This can lead to
// requests being unbalanced among Coder instances.
runnerClient, err := loadtestutil.DupClientCopyingHeaders(client, BypassHeader)
if err != nil {
return xerrors.Errorf("create runner client: %w", err)
}
var runner harness.Runnable = dynamicparameters.NewRunner(runnerClient, cfg)
if tracingEnabled {
runner = &runnableTraceWrapper{
tracer: tracer,
spanName: fmt.Sprintf("%s/%d/%d", dynamicParametersTestName, i, j),
runner: runner,
}
}
th.AddRun(dynamicParametersTestName, fmt.Sprintf("%d/%d", j, i), runner)
}
}
testCtx, testCancel := timeoutStrategy.toContext(ctx)
defer testCancel()
err = th.Run(testCtx)
if err != nil {
return xerrors.Errorf("run test harness: %w", err)
}
res := th.Results()
for _, o := range outputs {
err = o.write(res, inv.Stdout)
if err != nil {
return xerrors.Errorf("write output %q to %q: %w", o.format, o.path, err)
}
}
return nil
},
}
cmd.Options = serpent.OptionSet{
{
Flag: "template",
Description: "Name of the template to use. If it does not exist, it will be created.",
Default: "scaletest-dynamic-parameters",
Value: serpent.StringOf(&templateName),
},
{
Flag: "concurrent-evaluations",
Description: "Number of concurrent dynamic parameter evaluations to perform.",
Default: "100",
Value: serpent.Int64Of(&numEvals),
},
{
Flag: "provisioner-tag",
Description: "Specify a set of tags to target provisioner daemons.",
Value: serpent.StringArrayOf(&provisionerTags),
},
}
orgContext.AttachOptions(cmd)
output.attach(&cmd.Options)
tracingFlags.attach(&cmd.Options)
prometheusFlags.attach(&cmd.Options)
timeoutStrategy.attach(&cmd.Options)
return cmd
}