Unittest recover

paddle/fluid/distributed/ps/README.md

@@ -1,3 +1,39 @@
 # 目录说明
 
-> 成型之后，上级目录的 table、thirdparty、table、service 目录可以删除，communicator_common.h 、fleet.cc、fleet.h 删除
+Table: for param storage and update
+-----MemorySparseTable: table for sparse param, used in cpu async mode
+-----MemoryDenseTable: table for dense param, used in cpu async/geo mode
+-----MemorySparseGeoTable: table for sparse param, used in cpu async mode
+-----CommonGraphTable: table used for graph learning
+-----BarrierTable: table for barrier function, used in cpu sync mode
+-----TensorTable: table which run program, used for learning rate decay only
+
+ValueAccessor: for pull param and push gradient
+-----CtrCommonAccessor: pull/push value with show/click, float type
+-----DownpourCtrDoubleAccessor: same as CtrCommonAccessor, other than show/click with double type
+-----SparseAccessor: used for common embedding, pull value without show/click, push value with show/click
+-----CommMergeAccessor: used for dense table only, for get param dim
+
+PsService(proto): for server to handle request
+-----PsBaseService
+----------BrpcPsService: for cpu dnn training task
+----------GraphBrpcService: for graph learning
+-----HeterService: for dnn training task with heterogeneous computing resources
+
+PSServer: recv request from trainer and handle it by service
+-----BrpcPsServer: for cpu dnn training task
+-----GraphBrpcServer: for graph learning
+-----PsLocalServer: for GpuPS
+
+HeterServer: for HeterPS
+
+PSClient: pull param and push gradient for trainer
+-----BrpcPsClient: for cpu dnn training task
+----------GraphBrpcClient: for graph learning
+-----PsLocalClient: for GpuPS
+
+HeterClient: for HeterPS
+
+PSCore: Wrapper for InitServer
+
+GraphPyService: for graph learning