Created by: helinwang

After made this change

--- a/go/pserver/client/client_test.go
+++ b/go/pserver/client/client_test.go

-       const numParameter = 100
+       const numParameter = 1000

The following crash will happen during unit test:

INFO[0000] New Optimizer Created with config:            ConfigSize=50 ElementType=4 ParamSize=25000 StateSize=0
fatal error: unexpected signal during runtime execution
[signal SIGSEGV: segmentation violation code=0x2 addr=0x7f326404b000 pc=0x8da2b8]

runtime stack:
runtime.throw(0xa63d61, 0x2a)
	/usr/local/go/src/runtime/panic.go:596 +0x95
runtime.sigpanic()
	/usr/local/go/src/runtime/signal_unix.go:274 +0x2db

goroutine 2446 [syscall, locked to thread]:
runtime.cgocall(0x8d54b0, 0xc423f0a920, 0xa62dfa)
	/usr/local/go/src/runtime/cgocall.go:131 +0xe2 fp=0xc423f0a8e0 sp=0xc423f0a8a0
github.com/PaddlePaddle/Paddle/go/pserver._Cfunc_paddle_update_parameter(0x7f32640437b0, 0xc400000004, 0xc424a88000, 0x2454, 0x0)
	github.com/PaddlePaddle/Paddle/go/pserver/_obj/_cgo_gotypes.go:140 +0x4d fp=0xc423f0a920 sp=0xc423f0a8e0
github.com/PaddlePaddle/Paddle/go/pserver.(*optimizer).UpdateParameter.func1(0xc423a20ec0, 0x5, 0x4, 0xc424a88000, 0x9150, 0x9150, 0x7f32640437b0, 0x4, 0xc424a88000, 0x2454, ...)
	/root/gopath/src/github.com/PaddlePaddle/Paddle/go/pserver/optimizer.go:81 +0x110 fp=0xc423f0a960 sp=0xc423f0a920
github.com/PaddlePaddle/Paddle/go/pserver.(*optimizer).UpdateParameter(0xc420406a50, 0xc423a20ec0, 0x5, 0x4, 0xc424a88000, 0x9150, 0x9150, 0xc423f0aa78, 0x48faa6)
	/root/gopath/src/github.com/PaddlePaddle/Paddle/go/pserver/optimizer.go:81 +0xb3 fp=0xc423f0aa10 sp=0xc423f0a960
github.com/PaddlePaddle/Paddle/go/pserver.(*Service).SendGrad(0xc420148240, 0xc423a20ec0, 0x5, 0x4, 0xc424a88000, 0x9150, 0x9150, 0xc423a20ec8, 0x0, 0x0)
	/root/gopath/src/github.com/PaddlePaddle/Paddle/go/pserver/service.go:194 +0x11f fp=0xc423f0aa88 sp=0xc423f0aa10
runtime.call128(0xc42007c3f0, 0xc42020e008, 0xc423c85450, 0x4000000050)
	/usr/local/go/src/runtime/asm_amd64.s:516 +0x66 fp=0xc423f0ab18 sp=0xc423f0aa88
reflect.Value.call(0xc420076f00, 0xc42020e008, 0x13, 0xa4c595, 0x4, 0xc423f0af20, 0x3, 0x3, 0xa54b5f, 0x10, ...)
	/usr/local/go/src/reflect/value.go:434 +0x91f fp=0xc423f0ae60 sp=0xc423f0ab18
reflect.Value.Call(0xc420076f00, 0xc42020e008, 0x13, 0xc4238d7f20, 0x3, 0x3, 0x8d3314, 0xc42019b280, 0xa54b5f)
	/usr/local/go/src/reflect/value.go:302 +0xa4 fp=0xc423f0aec8 sp=0xc423f0ae60
net/rpc.(*service).call(0xc420148300, 0xc420148280, 0xc4201ec9a0, 0xc42021e080, 0xc42459c7c0, 0x9e7a60, 0xc424a7e030, 0x199, 0x967000, 0xc423a20ec8, ...)
	/usr/local/go/src/net/rpc/server.go:387 +0x144 fp=0xc423f0af78 sp=0xc423f0aec8
runtime.goexit()
	/usr/local/go/src/runtime/asm_amd64.s:2197 +0x1 fp=0xc423f0af80 sp=0xc423f0af78
created by net/rpc.(*Server).ServeCodec
	/usr/local/go/src/net/rpc/server.go:481 +0x404