I noticed that growslice() shows up in the cpuprofile.
Avoiding slice append for the private jey copy gives a 0.6% speedup:
gocryptfs/internal/speed$ benchstat old new
name old time/op new time/op delta
StupidXchacha-4 5.68µs ± 0% 5.65µs ± 0% -0.63% (p=0.008 n=5+5)
name old speed new speed delta
StupidXchacha-4 721MB/s ± 0% 725MB/s ± 0% +0.63% (p=0.008 n=5+5)
2% performance improvement, almost for free.
gocryptfs/internal/speed$ benchstat old new
name old time/op new time/op delta
StupidXchacha-4 5.82µs ± 0% 5.68µs ± 0% -2.37% (p=0.008 n=5+5)
name old speed new speed delta
StupidXchacha-4 704MB/s ± 0% 721MB/s ± 0% +2.43% (p=0.008 n=5+5)
Gets the decryption speed to the same level as the
encryption speed.
internal/speed$ benchstat old.txt new.txt
name old time/op new time/op delta
StupidXchacha-4 732MB/s ± 0% 740MB/s ± 0% ~ (p=1.000 n=1+1)
StupidXchachaDecrypt-4 602MB/s ± 0% 741MB/s ± 0% ~ (p=1.000 n=1+1)
Go has a high overhead for each C call, so batch
all openssl operations in the new C function chacha20poly1305_seal.
Benchmark results:
internal/speed$ go test -bench BenchmarkStupidXchacha -count 10 > old.txt
internal/speed$ go test -bench BenchmarkStupidXchacha -count 10 > new.txt
internal/speed$ benchstat old.txt new.txt
name old time/op new time/op delta
StupidXchacha-4 8.79µs ± 1% 7.25µs ± 1% -17.54% (p=0.000 n=10+10)
name old speed new speed delta
StupidXchacha-4 466MB/s ± 1% 565MB/s ± 1% +21.27% (p=0.000 n=10+10)
Our git version is v2+ for some time now, but go.mod
still declared v1. Hopefully making both match makes
https://pkg.go.dev/github.com/rfjakob/gocryptfs/v2 work.
All the import paths have been fixed like this:
find . -name \*.go | xargs sed -i s%github.com/rfjakob/gocryptfs/%github.com/rfjakob/gocryptfs/v2/%
Everything except the
if err2.Err == syscall.EOPNOTSUPP
case. Gets too confusing when collapsed into a single line.
Issues were:
$ golangci-lint run --disable-all --enable gosimple
mount.go:473:2: S1008: should use 'return strings.HasPrefix(v, "fusermount version")' instead of 'if strings.HasPrefix(v, "fusermount version") { return true }; return false' (gosimple)
if strings.HasPrefix(v, "fusermount version") {
^
cli_args.go:258:5: S1002: should omit comparison to bool constant, can be simplified to `args.forcedecode` (gosimple)
if args.forcedecode == true {
^
cli_args.go:263:6: S1002: should omit comparison to bool constant, can be simplified to `args.aessiv` (gosimple)
if args.aessiv == true {
^
cli_args.go:267:6: S1002: should omit comparison to bool constant, can be simplified to `args.reverse` (gosimple)
if args.reverse == true {
^
internal/stupidgcm/stupidgcm.go:227:6: S1002: should omit comparison to bool constant, can be simplified to `g.forceDecode` (gosimple)
if g.forceDecode == true {
^
gocryptfs-xray/xray_tests/xray_test.go:23:5: S1004: should use !bytes.Equal(out, expected) instead (gosimple)
if bytes.Compare(out, expected) != 0 {
^
gocryptfs-xray/xray_tests/xray_test.go:40:5: S1004: should use !bytes.Equal(out, expected) instead (gosimple)
if bytes.Compare(out, expected) != 0 {
^
gocryptfs-xray/paths_ctlsock.go:34:20: S1002: should omit comparison to bool constant, can be simplified to `!eof` (gosimple)
for eof := false; eof == false; line++ {
^
tests/reverse/xattr_test.go:19:2: S1008: should use 'return err2.Err != syscall.EOPNOTSUPP' instead of 'if err2.Err == syscall.EOPNOTSUPP { return false }; return true' (gosimple)
if err2.Err == syscall.EOPNOTSUPP {
^
internal/fusefrontend/node.go:459:45: S1002: should omit comparison to bool constant, can be simplified to `!nameFileAlreadyThere` (gosimple)
if nametransform.IsLongContent(cName2) && nameFileAlreadyThere == false {
^
tests/xattr/xattr_integration_test.go:221:2: S1008: should use 'return err2.Err != syscall.EOPNOTSUPP' instead of 'if err2.Err == syscall.EOPNOTSUPP { return false }; return true' (gosimple)
if err2.Err == syscall.EOPNOTSUPP {
^
tests/test_helpers/helpers.go:338:19: S1002: should omit comparison to bool constant, can be simplified to `open` (gosimple)
if err != nil && open == true {
^
tests/matrix/concurrency_test.go:121:7: S1004: should use !bytes.Equal(buf, content) instead (gosimple)
if bytes.Compare(buf, content) != 0 {
^
We used to prefer openssl in this situation, which
used to make sense, but now Go gained an optimized
assembly implementation for aes-gcm on arm64 with
aes instructions:
root@q1:~/go/src/github.com/rfjakob/gocryptfs# ./gocryptfs -speed
gocryptfs v1.7.1-46-g73436d9; go-fuse v1.0.1-0.20190319092520-161a16484456; 2020-04-13 go1.14.2 linux/arm64
AES-GCM-256-OpenSSL 212.30 MB/s (selected in auto mode)
AES-GCM-256-Go 452.30 MB/s
AES-SIV-512-Go 100.25 MB/s
XChaCha20-Poly1305-Go 137.35 MB/s
https://github.com/rfjakob/gocryptfs/issues/452
Now that I have discovered golang.org/x/sys/cpu and that Go
versions below 1.6 are uncommon, there was not much useful
code left in prefer_openssl.
Merge the remains into stupidgcm.
On MacOS, building and testing without openssl is much easier.
The tests should skip tests that fail because of missing openssl
instead of aborting.
Fixes https://github.com/rfjakob/gocryptfs/issues/123
Matéo Duparc
Jakob Unterwurzacher