crypto/tls: performance slow on windows/386

[RichardLaos]

What version of Go are you using (go version)?

c:\Go386\go\bin>go version
go version go1.14.6 windows/386

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

c:\Go386\go\bin>go env
set GO111MODULE=
set GOARCH=386
set GOBIN=
set GOCACHE=C:\Users\rlaos\AppData\Local\go-build
set GOENV=C:\Users\rlaos\AppData\Roaming\go\env
set GOEXE=.exe
set GOFLAGS=
set GOHOSTARCH=386
set GOHOSTOS=windows
set GOINSECURE=
set GONOPROXY=
set GONOSUMDB=
set GOOS=windows
set GOPATH=C:\Users\rlaos\go
set GOPRIVATE=
set GOPROXY=https://proxy.golang.org,direct
set GOROOT=c:\Go386\go
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLDIR=c:\Go386\go\pkg\tool\windows_386
set GCCGO=gccgo
set GO386=sse2
set AR=ar
set CC=gcc
set CXX=g++
set CGO_ENABLED=1
set GOMOD=
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-m32 -mthreads -fmessage-length=0 -fdebug-prefix-map=C:\Users\rlaos\AppData\Local\Temp\go-build312903914=/tmp/go-build -gno-record-gcc-switches

What did you do?

Ran crypto/tls BenchmarkThroughput

What did you expect to see?

Benchmark results similar to other platforms

What did you see instead?

Slower than expected benchmarks

c:\Go386\go\bin>go test crypto/tls -bench BenchmarkThroughput
goos: windows
goarch: 386
pkg: crypto/tls
BenchmarkThroughput/MaxPacket/1MB/TLSv12-8            12          85109717 ns/op          12.32 MB/s
BenchmarkThroughput/MaxPacket/1MB/TLSv13-8            12          90715292 ns/op          11.56 MB/s
BenchmarkThroughput/MaxPacket/2MB/TLSv12-8             6         182682667 ns/op          11.48 MB/s
BenchmarkThroughput/MaxPacket/2MB/TLSv13-8             6         167867017 ns/op          12.49 MB/s
BenchmarkThroughput/MaxPacket/4MB/TLSv12-8             3         350089833 ns/op          11.98 MB/s
BenchmarkThroughput/MaxPacket/4MB/TLSv13-8             3         344346567 ns/op          12.18 MB/s
BenchmarkThroughput/MaxPacket/8MB/TLSv12-8             2         752240000 ns/op          11.15 MB/s
BenchmarkThroughput/MaxPacket/8MB/TLSv13-8             2         740517600 ns/op          11.33 MB/s
BenchmarkThroughput/MaxPacket/16MB/TLSv12-8            1        1527828300 ns/op          10.98 MB/s
BenchmarkThroughput/MaxPacket/16MB/TLSv13-8            1        1508538200 ns/op          11.12 MB/s
BenchmarkThroughput/MaxPacket/32MB/TLSv12-8            1        2851125400 ns/op          11.77 MB/s
BenchmarkThroughput/MaxPacket/32MB/TLSv13-8            1        2923947500 ns/op          11.48 MB/s
BenchmarkThroughput/MaxPacket/64MB/TLSv12-8            1        5856113800 ns/op          11.46 MB/s
BenchmarkThroughput/MaxPacket/64MB/TLSv13-8            1        5691605000 ns/op          11.79 MB/s
BenchmarkThroughput/DynamicPacket/1MB/TLSv12-8                13          93452846 ns/op          11.22 MB/s
BenchmarkThroughput/DynamicPacket/1MB/TLSv13-8                12          89222967 ns/op          11.75 MB/s
BenchmarkThroughput/DynamicPacket/2MB/TLSv12-8                 6         174278867 ns/op          12.03 MB/s
BenchmarkThroughput/DynamicPacket/2MB/TLSv13-8                 6         184205067 ns/op          11.38 MB/s
BenchmarkThroughput/DynamicPacket/4MB/TLSv12-8                 3         371415800 ns/op          11.29 MB/s
BenchmarkThroughput/DynamicPacket/4MB/TLSv13-8                 3         345000733 ns/op          12.16 MB/s
BenchmarkThroughput/DynamicPacket/8MB/TLSv12-8                 2         741865300 ns/op          11.31 MB/s
BenchmarkThroughput/DynamicPacket/8MB/TLSv13-8                 2         690233200 ns/op          12.15 MB/s
BenchmarkThroughput/DynamicPacket/16MB/TLSv12-8                1        1449565400 ns/op          11.57 MB/s
BenchmarkThroughput/DynamicPacket/16MB/TLSv13-8                1        1499601000 ns/op          11.19 MB/s
BenchmarkThroughput/DynamicPacket/32MB/TLSv12-8                1        3050847000 ns/op          11.00 MB/s
BenchmarkThroughput/DynamicPacket/32MB/TLSv13-8                1        2980453500 ns/op          11.26 MB/s
BenchmarkThroughput/DynamicPacket/64MB/TLSv12-8                1        5588348900 ns/op          12.01 MB/s
BenchmarkThroughput/DynamicPacket/64MB/TLSv13-8                1        5793084600 ns/op          11.58 MB/s
PASS
ok      crypto/tls      69.500s

[toothrot]

/cc @FiloSottile

[RichardLaos]

The benchmark is similar whether this is a native 32bit environment or the 386 release in a 64bit environment.