update doc

doc/FAQ.md

@@ -13,3 +13,6 @@
   client.set_rpc_timeout_ms(100000)
   client.connect(["127.0.0.1:9393"])
    ```
+
+- Q: 如何使用自己编译的Paddle Serving进行预测？
+  A：通过pip命令安装自己编译出的whl包，并设置SERVING_BIN环境变量为编译出的serving二进制文件路径。

doc/PERFORMANCE_OPTIM.md

@@ -14,7 +14,35 @@ Under the same conditions, the communication time of the HTTP prediction service
 
 Parameters for performance optimization:
 
+The memory/graphic memory optimization option is enabled by default in Paddle Serving, which can reduce the memory/video memory usage and usually does not affect performance. If you need to turn it off, you can use --mem_optim_off in the command line.
+
+r_optim can optimize the calculation graph and increase the inference speed. It is turned off by default and turned on by --ir_optim in the command line.
+
 | Parameters | Type | Default | Description                                                  |
 | ---------- | ---- | ------- | ------------------------------------------------------------ |
 | mem_optim_off  | - | - | Disable memory / graphic memory optimization                                   |
 | ir_optim   | - | -  | Enable analysis and optimization of calculation graph,including OP fusion, etc |
+
+
+For the mode of using Python code to start the prediction service, the API of the above two parameters is as follows:
+
+RPC Service
+```
+from paddle_serving_server import Server
+server = Server()
+...
+server.set_memory_optimize(mem_optim)
+server.set_ir_optimize(ir_optim)
+...
+```
+
+HTTP Service
+```
+from paddle_serving_server import WebService
+class NewService(WebService):
+...
+new_service = NewService(name="new")
+...
+new_service.prepare_server(mem_optim=True, ir_optim=False)
+...
+```

doc/PERFORMANCE_OPTIM_CN.md

@@ -14,7 +14,33 @@
 
 性能优化相关参数：
 
+Paddle Serving中默认开启内存/显存优化选项，可以减少对内存/显存的占用，通常不会对性能造成影响，如果需要关闭可以在命令行启动模式中使用--mem_optim_off。
+ir_optim可以优化计算图，提升推理速度，默认关闭，在命令行启动的模式中通过--ir_optim开启。
+
 | 参数      | 类型 | 默认值 | 含义                      |
 | --------- | ---- | ------ | -------------------------------- |
 | mem_optim_off | - | -  | 关闭内存/显存优化                |
 | ir_optim  | - | -  | 开启计算图分析优化，包括OP融合等 |
+
+
+对于使用Python代码启动预测服务的模式，以上两个参数的接口如下：
+RPC服务
+```
+from paddle_serving_server import Server
+server = Server()
+...
+server.set_memory_optimize(mem_optim)
+server.set_ir_optimize(ir_optim)
+...
+```
+
+HTTP服务
+```
+from paddle_serving_server import WebService
+class NewService(WebService):
+...
+new_service = NewService(name="new")
+...
+new_service.prepare_server(mem_optim=True, ir_optim=False)
+...
+```