4.5. 访问registry的指标数据（metrics）
OpenShift Container Registry 为 Prometheus metrics 提供了一个端点。Prometheus是一个独立的开源系统监视和警报工具包。
metrics 可以通过registry端点的/extensions/v2/metrics路径获得。
流程
您可以通过两种方式访问指标数据：运行指标数据查询或使用集群角色。
指标数据查询
运行指标查询，例如：
$ curl --insecure -s -u <user>:<secret> \ 1 https://image-registry.openshift-image-registry.svc:5000/extensions/v2/metrics | grep imageregistry | head -n 20输出示例
# HELP imageregistry_build_info A metric with a constant '1' value labeled by major, minor, git commit & git version from which the image registry was built. # TYPE imageregistry_build_info gauge imageregistry_build_info{gitCommit="9f72191",gitVersion="v3.11.0+9f72191-135-dirty",major="3",minor="11+"} 1 # HELP imageregistry_digest_cache_requests_total Total number of requests without scope to the digest cache. # TYPE imageregistry_digest_cache_requests_total counter imageregistry_digest_cache_requests_total{type="Hit"} 5 imageregistry_digest_cache_requests_total{type="Miss"} 24 # HELP imageregistry_digest_cache_scoped_requests_total Total number of scoped requests to the digest cache. # TYPE imageregistry_digest_cache_scoped_requests_total counter imageregistry_digest_cache_scoped_requests_total{type="Hit"} 33 imageregistry_digest_cache_scoped_requests_total{type="Miss"} 44 # HELP imageregistry_http_in_flight_requests A gauge of requests currently being served by the registry. # TYPE imageregistry_http_in_flight_requests gauge imageregistry_http_in_flight_requests 1 # HELP imageregistry_http_request_duration_seconds A histogram of latencies for requests to the registry. # TYPE imageregistry_http_request_duration_seconds summary imageregistry_http_request_duration_seconds{method="get",quantile="0.5"} 0.01296087 imageregistry_http_request_duration_seconds{method="get",quantile="0.9"} 0.014847248 imageregistry_http_request_duration_seconds{method="get",quantile="0.99"} 0.015981195 imageregistry_http_request_duration_seconds_sum{method="get"} 12.260727916000022- 1
<user>可以是任意的，但<secret>必须与registry配置中指定的值匹配。
集群角色
如果还没有一个访问指标的集群角色，创建一个集群角色：
$ cat <<EOF | oc create -f - apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole metadata: name: prometheus-scraper rules: - apiGroups: - image.openshift.io resources: - registry/metrics verbs: - get EOF
将此角色添加到用户，运行以下命令：
$ oc adm policy add-cluster-role-to-user prometheus-scraper <username>
使用集群角色访问指标数据。配置文件中与指标数据相关的部分应如下所示：
openshift: version: 1.0 metrics: enabled: true ...
