roachprod: add parca-agent start and stop

Adds the ability to install the Parca Agent. For more details on the
capabilities of Parca and Polaris Signals see [1] & [2].

[1]: https://github.com/parca-dev/parca
[2]: https://www.polarsignals.com/docs/overview

Epic: None
Release note: None

Author: herkolategan

pkg/BUILD.bazel

@@ -1709,6 +1709,7 @@ GO_TARGETS = [
     "//pkg/roachprod/agents/fluentbit:fluentbit",
     "//pkg/roachprod/agents/opentelemetry:opentelemetry",
     "//pkg/roachprod/agents/opentelemetry:opentelemetry_test",
+    "//pkg/roachprod/agents/parca:parca",
     "//pkg/roachprod/blobfixture:blobfixture",
     "//pkg/roachprod/blobfixture:blobfixture_test",
     "//pkg/roachprod/cloud:cloud",

pkg/roachprod/BUILD.bazel

@@ -18,6 +18,7 @@ go_library(
         "//pkg/cmd/roachprod/grafana",
         "//pkg/roachprod/agents/fluentbit",
         "//pkg/roachprod/agents/opentelemetry",
+        "//pkg/roachprod/agents/parca",
         "//pkg/roachprod/cloud",
         "//pkg/roachprod/config",
         "//pkg/roachprod/install",

pkg/roachprod/agents/parca/BUILD.bazel

@@ -0,0 +1,14 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "parca",
+    srcs = ["parca.go"],
+    embedsrcs = ["files/parca-agent.service"],
+    importpath = "github.com/cockroachdb/cockroach/pkg/roachprod/agents/parca",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//pkg/roachprod/install",
+        "//pkg/roachprod/logger",
+        "@com_github_cockroachdb_errors//:errors",
+    ],
+)

pkg/roachprod/agents/parca/files/parca-agent.service

@@ -0,0 +1,22 @@
+[Unit]
+Description=Parca Agent
+Documentation=https://www.parca.dev/docs/systemd
+Requires=network.target
+After=network.target
+
+[Service]
+Type=simple
+User=root
+Group=root
+
+ExecStart=/opt/parca/parca-agent --remote-store-bearer-token-file=/opt/parca/parca.token --remote-store-address=grpc.polarsignals.com:443 --http-address=:7071
+
+Restart=on-failure
+RestartSec=10
+
+StandardOutput=syslog
+StandardError=syslog
+SyslogIdentifier=parcaagent
+
+[Install]
+WantedBy=multi-user.target

pkg/roachprod/agents/parca/parca.go

@@ -0,0 +1,53 @@
+// Copyright 2025 The Cockroach Authors.
+//
+// Use of this software is governed by the CockroachDB Software License
+// included in the /LICENSE file.
+
+package parca
+
+import (
+	"context"
+	_ "embed"
+
+	"github.com/cockroachdb/cockroach/pkg/roachprod/install"
+	"github.com/cockroachdb/cockroach/pkg/roachprod/logger"
+	"github.com/cockroachdb/errors"
+)
+
+//go:embed files/parca-agent.service
+var parcaAgentSystemdUnit string
+
+type Config struct {
+	Token string
+}
+
+// Install installs the Parca Agent on the cluster and starts it as a systemd service.
+func Install(ctx context.Context, l *logger.Logger, c *install.SyncedCluster, config Config) error {
+
+	if err := c.PutString(ctx, l, c.Nodes, config.Token, "/tmp/parca.token", 0644); err != nil {
+		return errors.Wrapf(err, "failed writing token")
+	}
+	if err := c.PutString(ctx, l, c.Nodes, parcaAgentSystemdUnit, "/tmp/parca-agent.service", 0644); err != nil {
+		return errors.Wrapf(err, "failed writing parca agent systemd unit file")
+	}
+
+	if err := c.Run(ctx, l, l.Stdout, l.Stderr, install.WithNodes(c.Nodes),
+		"download and set up parca-agent", `sudo mkdir -p /opt/parca
+curl -sL https://github.com/parca-dev/parca-agent/releases/download/v0.42.0/parca-agent_0.42.0_$(uname -s)_$(uname -m) -o /tmp/parca-agent
+sudo mv /tmp/parca-agent /opt/parca/parca-agent && chmod +x /opt/parca/parca-agent
+sudo mv /tmp/parca.token /opt/parca/parca.token
+sudo mv /tmp/parca-agent.service /etc/systemd/system/parca-agent.service
+sudo systemctl daemon-reload && sudo systemctl enable parca-agent && sudo systemctl restart parca-agent
+`); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// Stop stops the Parca Agent on the cluster and removes it from systemd.
+func Stop(ctx context.Context, l *logger.Logger, c *install.SyncedCluster) error {
+	return c.Run(ctx, l, l.Stdout, l.Stderr,
+		install.WithNodes(c.Nodes).WithShouldRetryFn(install.AlwaysTrue), "parca-agent-stop",
+		"sudo systemctl disable parca-agent && sudo systemctl stop parca-agent")
+}

pkg/roachprod/roachprod.go

@@ -33,6 +33,7 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/cmd/roachprod/grafana"
 	"github.com/cockroachdb/cockroach/pkg/roachprod/agents/fluentbit"
 	"github.com/cockroachdb/cockroach/pkg/roachprod/agents/opentelemetry"
+	"github.com/cockroachdb/cockroach/pkg/roachprod/agents/parca"
 	"github.com/cockroachdb/cockroach/pkg/roachprod/cloud"
 	"github.com/cockroachdb/cockroach/pkg/roachprod/config"
 	"github.com/cockroachdb/cockroach/pkg/roachprod/install"
@@ -2596,6 +2597,40 @@ func StopOpenTelemetry(ctx context.Context, l *logger.Logger, clusterName string
 	return opentelemetry.Stop(ctx, l, c)
 }
 
+// StartParcaAgent starts a Parca Agent on the cluster.
+func StartParcaAgent(
+	ctx context.Context, l *logger.Logger, clusterName string, config parca.Config,
+) error {
+	if config.Token == "" {
+		return errors.New("Token cannot be empty")
+	}
+
+	if err := LoadClusters(); err != nil {
+		return err
+	}
+
+	c, err := newCluster(l, clusterName)
+	if err != nil {
+		return err
+	}
+
+	return parca.Install(ctx, l, c, config)
+}
+
+// StopParcaAgent stops the Parca Agent on the cluster.
+func StopParcaAgent(ctx context.Context, l *logger.Logger, clusterName string) error {
+	if err := LoadClusters(); err != nil {
+		return err
+	}
+
+	c, err := newCluster(l, clusterName)
+	if err != nil {
+		return err
+	}
+
+	return parca.Stop(ctx, l, c)
+}
+
 // DestroyDNS destroys the DNS records for the given cluster.
 func DestroyDNS(ctx context.Context, l *logger.Logger, clusterName string) error {
 	c, err := GetClusterFromCache(l, clusterName)