add pprof doc for Karmada

Signed-off-by: Poor12 <shentiecheng@huawei.com>

docs/contributors/devel/profiling-karmada.md

@@ -0,0 +1,61 @@
+# Profiling Karmada
+
+## Enable profiling
+
+To profile Karmada components running inside a Kubernetes pod, set --enable-pprof flag to true in the yaml of Karmada components. 
+The default profiling address is 127.0.0.1:6060, and it can be configured via `--profiling-bind-address`.
+The components which are compiled by the Karmada source code support the flag above, including `Karmada-agent`, `Karmada-aggregated-apiserver`, `Karmada-controller-manager`, `Karmada-descheduler`, `Karmada-search`, `Karmada-scheduler`, `Karmada-scheduler-estimator`, `Karmada-webhook`.
+
+```
+--enable-pprof                                                                                                                                                                
+                Enable profiling via web interface host:port/debug/pprof/.
+--profiling-bind-address string                                                                                                                                               
+                The TCP address for serving profiling(e.g. 127.0.0.1:6060, :6060). This is only applicable if profiling is enabled. (default ":6060")
+
+```
+
+## Expose the endpoint at the local port
+
+You can get at the application in the pod by port forwarding with kubectl, for example:
+
+```shell
+$ kubectl -n karmada-system get pod
+NAME                                          READY   STATUS    RESTARTS   AGE
+karmada-controller-manager-7567b44b67-8kt59   1/1     Running   0          19s
+...
+```
+
+```shell
+$ kubectl -n karmada-system port-forward karmada-controller-manager-7567b44b67-8kt59 6060
+Forwarding from 127.0.0.1:6060 -> 6060
+Forwarding from [::1]:6060 -> 6060
+```
+
+The HTTP endpoint will now be available as a local port.
+
+## Generate the data
+
+You can then generate the file for the memory profile with curl and pipe the data to a file:
+
+```shell
+$ curl http://localhost:6060/debug/pprof/heap  > heap.pprof
+```
+
+Generate the file for the CPU profile with curl and pipe the data to a file (7200 seconds is two hours):
+
+```shell
+curl "http://localhost:6060/debug/pprof/profile?seconds=7200" > cpu.pprof
+```
+
+## Analyze the data
+
+To analyze the data:
+
+```shell
+go tool pprof heap.pprof
+```
+
+## Read more about profiling
+
+1. [Profiling Golang Programs on Kubernetes](https://danlimerick.wordpress.com/2017/01/24/profiling-golang-programs-on-kubernetes/)
+2. [Official Go blog](https://blog.golang.org/pprof)