Go 1.12 Released

https://blog.golang.org/go1.12

by crawshaw • 7 years ago

295 113 7 years ago

blog.golang.org

bithavoc• 7 years ago

This is so great, although I tried to update my docker container and the official docker container is still in rc.

bradfitz3• 7 years ago

The Go team doesn't own the official Docker containers and we don't notify the maintainers when we do a release. We probably should.

pythonist5• 7 years ago

Maybe they can use https://NewReleases.io to track Go releases.

mrweasel• 7 years ago

I had to check what the Go docker image does.... It does NOTHING, it just builds and installs Go, why would you even need a container for this?

fwip• 7 years ago

Either as a base for a development environment, or a disposable container to compile your go programs.

For example, compiling your program with a different version of Go can be done just by changing the tag on your compile command, and doesn't require that you have any development tools or compilers installed on your machine (except docker).

dfinninger• 7 years ago

It's super useful to be able to build go binaries in a CI system. It provides the Go toolchain in a container so that you can just use it as a mini-executor. For instance, in Jenkins you can hook up the Jenkins master to a Kubernetes cluster and run your CI in a docker container. The Go docker container is great for this. I can run `go test ...` etc.

Also, when building a container with a Go binary, it's a great base to build from. You can use Docker Multistage Builds[1] to build your binary in the Go container, then copy it out into a minimal container all in the same Dockerfile.

[1] https://docs.docker.com/develop/develop-images/multistage-bu...

saagarjha• 7 years ago

libSystem is now used when making syscalls on Darwin, ensuring forward-compatibility with future versions of macOS and iOS. The switch to libSystem triggered additional App Store checks for private API usage. Since it is considered private, syscall.Getdirentries now always fails with ENOSYS on iOS.

Hooray! I'm surprised it took as long as it did, since IIRC this was something that broke constantly…

weberc24• 7 years ago

I’ve only heard of one or two breakages...

geodel• 7 years ago

Well, in internet parlance its broken every single time. On the other hand if I like something then broken thing will always work flawlessly for me

FiloSottile5• 7 years ago

_o/ hello HN, this release ships with seamless opt-in support for TLS 1.3 in crypto/tls. (Gated by the GODEBUG=tls13=1 environment variable.)

I'd be happy to answer any questions about it, or about the rest of the Go cryptography libraries!

tonymet• 7 years ago

I was curious about new features in tls1.3 and this doc was a good breakdown

https://www.cloudflare.com/learning-resources/tls-1-3/

crawshaw• 7 years ago

Any concerns exposing Go tls1.3 directly to the internet today?

Is 0-RTT on the roadmap for Go 1.13?

FiloSottile5• 7 years ago

crypto/tls is designed and developed to be fit to be exposed directly to the Internet. The advice I wrote here is mostly dated (I really need to write a follow-up), but it's still indicative: https://blog.gopheracademy.com/advent-2016/exposing-go-on-th...

[Updated to add] TLS 1.3 is opt-in because despite years of improvements, it can still hit compatibility issues with broken or legacy peers. (Search for "TLS 1.3" on the Go issue tracker if you are curious.)

0-RTT is blocked on figuring out good, safe APIs for it. I feel like I am 80% of the way there for servers (just have to figure out how to make it opt-in per http.Handler instead of opt-out), while for clients I have no idea how to fit resending in io.Writer.

mholt2• 7 years ago

I'll add, too, that anyone who wants to try TLS 1.3 right now can do so with the latest source builds of the Caddy web server. We just merged support for TLS 1.3 a few minutes after the Go 1.12 release: https://github.com/mholt/caddy/pull/2399

If you have a domain name pointed at your machine:

    $ caddy -host example.com

(Roughly equivalent to python -m SimpleHTTPServer but with HTTPS, and production-ready.)

Or if you just want to try things out:

    $ caddy "tls self_signed"

mappu• 7 years ago

I'm glad to see setting the env var in init() is enough to trigger this on - I'll be doing the same at $DAYJOB.

kodablah3• 7 years ago

I know and understand the philosophy behind limited exposure/customization of the handshake process. However, there is a lot of value in implementing TLS extensions, adding early data on client hello, etc. I saw [0] but didn't see any details. Is it possible/reasonable to extract some of the internals to /x/crypto/tls or similar? Or is it either too hard to maintain or is there just too much fear about misuse?

0 - https://github.com/golang/go/issues/25807

FiloSottile5• 7 years ago

Most of it is that it's harder to come up with useful, safe, not overfitting APIs the deeper you go into internals. For example, registering extensions is rarely useful on its own as extensions are allowed to change literally anything else in the protocol, and without hooks for everything else you did not get much value.

But! Hearing about what people would like to do and then putting together an API if it makes sense is my job! So please do open an issue saying what you'd like to do but can't.

For example, I mean to extract Client Hello parsing and a capturing middleware net.Conn, as a lot of passive things can be implemented that way.

yesenadam3• 7 years ago

OK thanks, basic question, but.. What is TLS?

wereHamster• 7 years ago

The S in HTTPS. The technology that is securing your HTTP connections, but also used by other protocols.

https://en.wikipedia.org/wiki/Transport_Layer_Security

giovannibajo1• 7 years ago

Is there any performance issue that we should be aware of when turning on TLS 1.3? Go's standard library has many assembly implementations (to leverage CPU special opcodes). What is the speed of the TLS 1.3 crypto stack in Go?

lazard• 7 years ago

How can we help with getting support for Ed25519 in crypto/x509 and crypto/tls?

sodpoisadfio• 7 years ago

https://github.com/golang/go/issues/25355

mspecter• 7 years ago

What's the plan for pairing based curves now that the Extended Tower Number Field Sieve has made BN256 unusable for many applications[1]? Do you plan on integrating BLS curves any time soon?

[1] see https://godoc.org/golang.org/x/crypto/bn256

boyter2• 7 years ago

Perfect timing for me. I was just about to push out a new release for my code counter https://github.com/boyter/scc

It appears to be ~3-4 ms faster when counting repositories like redis which is rather nice for me as a free speed boost. Probably related to the changes to GC listed here https://golang.org/doc/go1.12#runtime

scottlamb• 7 years ago

I'm impressed every release by Go's GC improvements. IIRC, they started with a terrible conservative GC. It was slow and (particularly on 32-bit platforms) ineffective. But then they made it increasingly precise, then targeted 10 ms pause times, then sub-millisecond, and so on. All with far fewer knobs than the Oracle JVM.

I understand there's still a cost compared to non-GCed languages, but I think it's mostly RAM usage (perhaps affecting CPU cache effectiveness and thus efficiency) rather than tail latency.

bpye3• 7 years ago

I feel that Go really excells in getting out of your way. I rarely find myself fighting with the language or runtime. The few occasions I have have been related to native interop and generally mean I'm having to look at the internal fields of slices or strings to modify data effeciently, and even that isn't too diffit.

kasey_junk3• 7 years ago

I haven’t checked since 1.10 but at that time you could definitely see what I presume was the impact of lack of compaction on heap allocations over time. That is allocations would take longer as your program ran longer.

This is mitigated quite a bit by how much gets stack allocated but I imagine there are workloads that this hampers a lot, in particular large in memory data sets.

That’s not to disagree with your point the GC improvements are great for my workloads but only to point out there is a cost to them.

pcwalton• 7 years ago

But then they made it increasingly precise, then targeted 10 ms pause times, then sub-millisecond, and so on. All with far fewer knobs than the Oracle JVM.

The number of "knobs" in Go's GC is the same as that of G1: max pause time and max memory usage. (HotSpot has more intuitive names for its configuration settings compared to Go's confusing names.) More importantly, Go's GC sacrifices a very large amount of throughput in pursuit of low latency at all costs. This is not a very good tradeoff for most applications.

See: https://blog.plan99.net/modern-garbage-collection-911ef4f8bd...

vanderZwan• 7 years ago

It appears to be ~3-4 ms faster when counting repositories like redis which is rather nice for me as a free speed boost.

Nice! Out of curiosity: what is the total running time? Or in other words: what is the average performance improvement in percentages?

boyter2• 7 years ago

Still testing but seems to be around 3% improvement for most cases I have tried.

networkimprov• 7 years ago

Go 1.12 fixes a bug in os.File.Sync() on MacOS, which didn't actually fsync() properly.

This affects several popular database libraries.

https://github.com/golang/go/issues/26650

tjpnz• 7 years ago

Is iOS a thing for Go?

angott• 7 years ago

You might be interested in this, although support is extremely limited and restricted to specific areas: https://github.com/golang/go/wiki/Mobile#building-and-deploy...

rhodysurf• 7 years ago

Sort of... it works with GoMobile but because it doesnt use LLVM there is no support for bitcode which means WatchOS and tvOS are off limits and maybe iOS someday.

steeleduncan• 7 years ago

Would this be solveable with go-llvm?

sandov2• 7 years ago

Something I consider off-putting about Go is that you need a Google account to contribute.

https://golang.org/doc/contribute.html

A contribution to Go is made through a Google account [...]. Google accounts can either be Gmail e-mail accounts, G Suite organization accounts, or accounts associated with an external e-mail address. [...]

Does anybody else feel the same way?

FiloSottile5• 7 years ago

You can now use plain GitHub PRs.

bradfitz3• 7 years ago

Yes and no. You can't agree to the CLA with just GitHub, IIRC.

wmf• 7 years ago

The fact that Go is mostly controlled by Google doesn't bother you, but that does?

(I consciously avoided getting a Gmail account for years until I bought an Android phone which requires such an account, so I understand where you're coming from but this issue seems meh to me.)

tssva• 7 years ago

(I consciously avoided getting a Gmail account for years until I bought an Android phone which requires such an account, so I understand where you're coming from but this issue seems meh to me.)

Gmail accounts are not required for Android phones. To utilize the Google services on an Android phone, which 99% of people will choose to do, a Google account is required.

A Google account can be but doesn't have to be a Gmail account. You can use any email address to create your Google account.

meruru• 7 years ago

Lineage and other custom Android versions don't have such requirement.

sandov2• 7 years ago

It doesn't bother me that it's "controlled" (someone has to lead the project anyway) by Google. being Google doesn't disqualify them from doing good things, but needing a Google account makes it seem like it's a closed community only for Googlers.

bouncycastle2• 7 years ago

Fmt will print maps out in sorted order? I guess that will confuse many newcomers even more

dx034• 7 years ago

Why should that confuse?

katnegermis• 7 years ago

I think he's referring to the fact that maps are iterated in random order. Now if you print them directly, you may be lead to believe that the order is _not_ random.

jxub• 7 years ago

This FOSDEM Francesc explained the rationale behind this change, and namely in order to have an easier time comparing maps while debugging.

entity34512• 7 years ago

To me it's a deeper issue that this and breaches the single responsibility principle.

fmt should only print, not manipulate the data it is asked to print.

I believe that the spec says that maps iterate over keys effectively at random and so that should be the result of any operation that iterates over keys.

martingxx• 7 years ago

The `fmt` packages is described as being for "formatted i/o". It seems that ordered maps, while not "i/o" is reasonable to describe as "formatting", so it's fine to do it in this package I think.

`fmt` has always made things look prettier, that's part of what formatting is about.

You could equally argue that `fmt` should not round floats or pad numbers with zeros or spaces.

sacado2• 7 years ago

It is not random, it is undeterminate. Any order follows that spec. Whether you display items in alphabetical order, in insertion order, randomly, or in any other way, you're good.

skywhopper3• 7 years ago

I'm confused about why this would be a problem, though. The majority of use cases I can think of for using fmt functions to render maps into strings would not be harmed in any way by presenting the map in sorted-key order. For my own use, such usage is mostly for debugging or logging purposes, in which case a sorted map is vastly preferable.

Given that the order of keys in a map is not guaranteed, I also wouldn't consider rendering them in a fixed order as "manipulation". The order of the keys is undefined, unimportant, program-wise. So presenting them in a certain order implies meaning (presumably there is one, whether it be creation order, LRU, or physical-memory layout). But if you know the keys are sorted before being printed, then you can continue to assume you don't know the actual order, or to put it another way, you can continue to suspend your disbelief about whether the keys are truly "unordered" in the system.

But to get back to practical concerns, I'm genuinely curious what harm you see from presenting the unordered keys in a predictable order that allows humans to get more use from the particular formatting?

tapirl• 7 years ago

The outputs of examples in many tutorials need to be corrected. :)

What not add a new format verb instead?

dilap• 7 years ago

Definitely a trade-off here between being handy for people that know what's gong on and confusing for beginners...

denormalfloat• 7 years ago

Glad to see syscall/js is still seeing updates. This seems like a excellent chance to share server and client code by being able to cross compile to wasm.

Go team: please reduce the binary size of wasm files!

agnivade• 7 years ago

The large binary size is mainly due to the Go runtime being packed into the binary itself. You can compile with "-ldflags -s" to make it slightly smaller. But it will almost never be comparable to Rust/Emscripten binary sizes.

OTOH, there is a new project called TinyGo (https://tinygo.org) which generates LLVM byte code from Go. This allows a subset of the Go spec, sans any GC or runtime, and generates binaries comparable to Rust/Emscripten.

1_000_000• 7 years ago

Honest question for core devs: why do you need my phone number and address to accept any code and pull requests?

fastbmk2• 7 years ago

Because Go is owned and controlled by Google, the company famous for personal data collection and misuse.

atonse• 7 years ago

Probably to keep a file of all contributors' contact information to get your permission if they ever wanted to do a license change?

bradfitz3• 7 years ago

I was the one who converted Google's CLA system from "Please fax us this form" to a web form. At the time (2007, 2008?) I added all the fields from the fax template to the web form. But we dropped the phone number & physical address years ago. And they were optional even before that.

Nowadays we ask for your name, email address, and optional GitHub username.

lsllc• 7 years ago

Wow, AIX support! nice!

clinta• 7 years ago

Very happy to read about the improvements in releasing memory back to the OS. Hopefully this will help prevent our go apps in containers from getting OOM killed.

arleny• 7 years ago

Been meaning to make the dive into learning Go for a while now. My semester is finally slowing down so about to make the jump. I'll be doing a lot of digging on my own, but please link any resources that you feel were helpful for you.

fastbmk2• 7 years ago

https://www.rust-lang.org/

Go 1.12 Released

Related Stories