Grafana 开源了一款 eBPF 采集器 Beyla

eBPF 的发展如火如荼，在可观测性领域大放异彩，Grafana 近期也发布了一款 eBPF 采集器，可以采集服务的 RED 指标，本文做一个尝鲜介绍，让读者有个大概了解。

eBPF 基础介绍可以参考我之前的文章《eBPF Hello world》。理论上，eBPF 可以拿到服务收到的请求信息，比如QPS、延迟、成功率等，这些数据对于应用级监控至关重要，Grafana Beyla 就是为此而生的。

要测试使用 Beyla 采集服务的 RED（Rate-Errors-Duration）指标，那首先得有个服务，这里我用的是 answer（ https://answer.flashcat.cloud ）论坛，你也可以自己搞一个简单的 http 服务，比如：

package main

import (
    "net/http"
    "strconv"
    "time"
)

func handleRequest(rw http.ResponseWriter, req *http.Request) {
    status := 200
    for k, v := range req.URL.Query() {
        if len(v) == 0 {
            continue
        }
        switch k {
        case "status":
            if s, err := strconv.Atoi(v[0]); err == nil {
                status = s
            }
        case "delay":
            if d, err := time.ParseDuration(v[0]); err == nil {
                time.Sleep(d)
            }
        }
    }
    rw.WriteHeader(status)
}

func main() {
    http.ListenAndServe(":8080",
                 http.HandlerFunc(handleRequest))
}

上面这个代码，保存成 server.go，然后用 go run server.go 即可运行，当然，前提是你机器上有 go 开发环境。这个小服务，可以接收两个参数，一个是 status，用来指定返回的 http 状态码，另一个是 delay，用来指定延迟多久返回，比如：

curl -v "http://localhost:8080/foo?status=404"

上面的命令，会返回 404 状态码，如果想延迟 1 秒返回，可以这样：

curl -v "http://localhost:8080/foo?delay=1s"

接下来，我们就可以使用 Beyla 采集这个服务的 RED 指标了。

下载 Beyla

我的机器上有 go 开发环境，所以我直接使用 go install 安装了，你也可以去 Beyla 的 release 页面下载二进制包，然后解压缩使用。

go install github.com/grafana/beyla/cmd/beyla@latest

运行 Beyla

使用下面的命令运行 Beyla：

$ BEYLA_PROMETHEUS_PORT=8999 PRINT_TRACES=true OPEN_PORT=8080 sudo -E beyla

或者直接使用 root 账号运行，比如我是这么跑的：

$ BEYLA_PROMETHEUS_PORT=8999 PRINT_TRACES=true OPEN_PORT=8080 beyla

解释一下这几个参数：

BEYLA_PROMETHEUS_PORT: Beyla 要监听的端口，通过这个端口暴露 metrics 指标数据
PRINT_TRACES: 是否打印 trace 日志
OPEN_PORT: Beyla 采集的目标服务监听的端口，这里是 8080，上面给出的那段 go server 的代码就是监听在 8080，我的机器上 answer 论坛程序也是监听在 8080，你要监控的程序如果不是监听在 8080，可以在换成你自己的端口

查看指标

运行之后，可以通过 curl 查看指标：

curl http://localhost:8999/metrics

返回的内容如下：

# HELP http_client_duration_seconds duration of HTTP service calls from the client side, in seconds
# TYPE http_client_duration_seconds histogram
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.005"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.01"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.025"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.05"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.075"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.1"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.25"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.5"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.75"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="1"} 0
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="2.5"} 1
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="5"} 1
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="7.5"} 1
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="10"} 1
http_client_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="+Inf"} 1
http_client_duration_seconds_sum{http_method="GET",http_status_code="200",service_name="answer"} 1.668771575
http_client_duration_seconds_count{http_method="GET",http_status_code="200",service_name="answer"} 1
# HELP http_client_request_size_bytes size, in bytes, of the HTTP request body as sent from the client side
# TYPE http_client_request_size_bytes histogram
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="32"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="64"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="128"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="256"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="512"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="1024"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="2048"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="4096"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="8192"} 1
http_client_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="+Inf"} 1
http_client_request_size_bytes_sum{http_method="GET",http_status_code="200",service_name="answer"} 0
http_client_request_size_bytes_count{http_method="GET",http_status_code="200",service_name="answer"} 1
# HELP http_server_duration_seconds duration of HTTP service calls from the server side, in seconds
# TYPE http_server_duration_seconds histogram
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0"} 0
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.005"} 201
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.01"} 789
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.025"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.05"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.075"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.1"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.25"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.5"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0.75"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="1"} 799
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="2.5"} 800
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="5"} 800
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="7.5"} 800
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="10"} 800
http_server_duration_seconds_bucket{http_method="GET",http_status_code="200",service_name="answer",le="+Inf"} 800
http_server_duration_seconds_sum{http_method="GET",http_status_code="200",service_name="answer"} 5.752096697000003
http_server_duration_seconds_count{http_method="GET",http_status_code="200",service_name="answer"} 800
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0"} 0
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.005"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.01"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.025"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.05"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.075"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.1"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.25"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.5"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0.75"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="1"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="2.5"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="5"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="7.5"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="10"} 1
http_server_duration_seconds_bucket{http_method="GET",http_status_code="302",service_name="answer",le="+Inf"} 1
http_server_duration_seconds_sum{http_method="GET",http_status_code="302",service_name="answer"} 0.001523002
http_server_duration_seconds_count{http_method="GET",http_status_code="302",service_name="answer"} 1
# HELP http_server_request_size_bytes size, in bytes, of the HTTP request body as received at the server side
# TYPE http_server_request_size_bytes histogram
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="0"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="32"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="64"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="128"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="256"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="512"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="1024"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="2048"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="4096"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="8192"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="200",service_name="answer",le="+Inf"} 800
http_server_request_size_bytes_sum{http_method="GET",http_status_code="200",service_name="answer"} 0
http_server_request_size_bytes_count{http_method="GET",http_status_code="200",service_name="answer"} 800
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="0"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="32"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="64"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="128"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="256"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="512"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="1024"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="2048"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="4096"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="8192"} 1
http_server_request_size_bytes_bucket{http_method="GET",http_status_code="302",service_name="answer",le="+Inf"} 1
http_server_request_size_bytes_sum{http_method="GET",http_status_code="302",service_name="answer"} 0
http_server_request_size_bytes_count{http_method="GET",http_status_code="302",service_name="answer"} 1
# HELP promhttp_metric_handler_errors_total Total number of internal errors encountered by the promhttp metric handler.
# TYPE promhttp_metric_handler_errors_total counter
promhttp_metric_handler_errors_total{cause="encoding"} 0
promhttp_metric_handler_errors_total{cause="gathering"} 0

这些指标就可以用采集器来抓了，比如 vmagent、categraf、prometheus 等，完事之后入库，使用 Grafana 展示分析即可，经常关注本公众号的读者对于这些知识应该比较熟悉了，这里不再赘述。Beyla 默认提供了一个 Grafana Dashboard，可以导入测试：https://github.com/grafana/beyla/tree/main/grafana。