Comment by jemeshsu | Hacker News Reader

Comment by jemeshsu | Hacker News Reader

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YouTube is using Golang http://code.google.com/p/vitess/. So 10% of Internet traffic now depends on it. I wouldn't call it not production ready.

From the project goal page:

"Go is miles ahead of C++ and Java in terms of expressibility and close in terms of performance. It is also relatively simple and has a straightforward interaction with Linux system calls.

The main drawback is also its strength - the garbage collector. vtocc has made spot optimizations to minimize most of the adverse effects of Go’s stop-the-world gc. At this point, we are trading some amount of performance for greater creativity and efficiency at lower layers. unless you’re trying to max out on qps for your servers, you should see acceptable performance from vtocc. Also, go’s garbage collector is being improved. So, this should only get better over time. Go’s existing mark-and-sweep garbage collector is sub-optimal for systems that use large amounts of static memory (like caches). In the case of vtocc, this would be the row cache. To alleviate this, we intend to use memcache for the time being. If the gc ends up addressing this, it should be fairly trivial to switch to an in-memory row cache. Note that the row cache functionality is not fully ready yet."

"Go is miles ahead of C++ and Java in terms of expressibility and close in terms of performance. It is also relatively simple and has a straightforward interaction with Linux system calls."

How can this be when Go lacks:

- enumerations

- exceptions

- generics

- dynamic loading

The short compilation times are possible in any language with modules.

Channels are available as part of concurrency libraries in Java, .NET, C++ and Erlang.

Goroutines are also possible in other languages, in form of continuations or task pools.

- It has a more general analogue to enumerations, one that does not add a lot of verbiage to the language spec. (http://play.golang.org/p/HSh4Ke3pCJ)

- It has an "exception" mechanism that is rarely used, in favour of error-valued returns. (http://blog.golang.org/2010/08/defer-panic-and-recover.html)

- Apparently, vitess didn't need generics. You'll notice a bit of casting here in their implementation of an LRU cache, but writing containers isn't exactly the main purpose of the library. I do admit I want generics, for the sole purpose of stopping people parroting that criticism without actually using the language. (http://code.google.com/p/vitess/source/browse/go/cache/lru_c...)

- Not sure what you mean here. If you mean a Go library is being loaded, then there's an issue for that, but one unlikely to be fixed in the short-term because of Go's unusual calling convention. If you mean Go loading a library at runtime, I don't know why you'd want this. Either way, static linking seems cleaner and more self contained to me.

"Short compilation times" being available in any language is total bull. Try building chromium or firefox in a reasonable amount of time, without a build cluster. Don't you think if there was a way to speed that up, the developers would make that priority 1?

Channel/Goroutines are of course available in all languages, Turing-completeness implies that they must. However, in practice, does all code in those languages make use of the same concurrency primitives? Do they read as nicely as Go does?

> Try building chromium or firefox in a reasonable amount of time

He wrote "in any language with modules". C++ doesn't have them.

Thanks.

I am not sure what it is up with these kids today, that only seem to know C and C++ as languages for native development.

There are many others out there that always had modules and fast compilation times.

Apologies. I misread your post because you were comparing Go to Java and C++, and I erroneously assumed the entire post was talking about those languages.

None of those things are really roadblocks to Getting Shit Done though, except maybe dynamic loading.

Go has plenty of support for global constant values that take the place of enumerations, even to the point of having an "iota" syntax to make initializing constants easier.

Exceptions are generally an anti-pattern in my opinion: a hack to get around the ability to return multiple values from a function, so that error conditions can be handled in-band. The other technical challenge exceptions sometimes provide -- guaranteed cleanup after code that might fail to execute -- can be handled by Go's deferred function execution.

Generics are a powerful abstraction, but Go has very good support for (un)boxed values and interfaces, so the only thing you would get from generics is a bit more type safety. The additional complexity required to support generics isn't worth it.

Dynamic loading is arguably a blocker for certain modes of development and distribution, but by not supporting dynamic loading, Go can make tremendous simplifications in its module system. Making the assumption that every go library is distributed in source form greatly reduces compatibility friction and runtime bugs. "DLL Hell" may be a "solved" problem on most systems nowadays, but there are a lot of moving parts to enable that.

The simplifications that Go makes are 100% worth it in my opinion. There is one place where Go sacrifices something that can't be replaced is that a stop-the-world garbage collector may be unacceptable for some applications. Other than that, codebases aren't actually served by having too much power in their languages, even if an individual programmer might be.

ioata is a poor man's solution to enumerations. Why should I do the work for the compiler?

Even C has enumerations, a language developed in 1972! This is how modern Go is.

The lack of generics makes everyone that writes generic data structure code like it was the 90's again. Copy-pasting code or writing template processors to generate code. Talk about evolution.

Dynamic loading is an important way to write modular applications that can be composed on run-time. Something like Eclipse would be impossible to write in Go, due to performance constrains of interprocess communication.

If Go did not had Google behind it, I doubt it would be noticed, it would fail as just another language.

Look how successful Limbo and Alef were. And Go is nothing more than a reinvention of them.

iota is much more general than just enumerations. http://golang.org/ref/spec#Iota

A neat example is using it to define constants for a bit field:

  const (
    A = 1 << iota
    B
    C
  )

It pollutes the global namespace, plus it is a common enumeration feature that you can give initial values to the enumeration elements, so I fail to see iota benefit.

There is no global namespace in Go. The fact that you don't know this trivial thing means you nothing about Go and only spread FUD.

Don't put words in my mouth please.

Each package has a global namespace, so each const has to be unique at the package level to avoid namespace collisions.

With proper enumerations, only the enumeration needs to be unique, while the enumeration elements would be scoped to the enumeration level, as most (not all) languages do.

You keep using that word, "global". I do not think it means what you think it means.

People who write data structures just give up type-safety when doing so. They don't copy-paste code or write template processors, afaik. A Left-leaning Red-Black Tree, for example: http://gopkgdoc.appspot.com/pkg/github.com/petar/GoLLRB/llrb

Holding up Eclipse as an example citing performance is perhaps not the best idea. And Chromium seems to do just fine (performance-wise) using IPC between renderer processes and the main process.

Go fanboys always cite Chromium as a gold example of process IPC and why dynamic loading is not required for plugins.

What people fail to see is that Chromium is just one use case.

An IDE for example, would explode memory wise if every single plugin would be a separate process. Then all plugins that require real time interaction with source code manipulation would suffer from heavy context switching.

Evidence of this memory explosion? Keep in mind that Go processes tend to take significantly less memory than Java processes, especially when dealing with IO related code, i.e. sockets (http://shootout.alioth.debian.org/u64q/benchmark.php?test=al...).

Sure, if you do it stupidly, and have a highlighter process per open document or something, it could add up over time. But if you share highlighter processes between documents, you have 1 process that you keep open for the lifetime of the application. A simple HTTP server in Go takes < 5 MB of RAM in its steady state, a server using domain sockets would probably be comparable. And even better, a bug in the highlighter doesn't mean your main application crashes. If it crashes, the parent merely restarts the process. Even better, its more secure, in the sense that you can run your highlighter with absolutely no OS privileges. Also, this allows for plugins written in any language that supports sockets.

All I'm saying is that there's no evidence that IPC isn't performant enough. And IPC comes with security, compatibility, and isolation advantages, to boot.

Note that I'm definitely not saying that dynamic loading wouldn't be nice. Do I miss it, when working with Go? Not for my use cases. "Plugins" for servers don't really make sense. But dismissing Go because it doesn't target every use-case at the moment is somewhat shortsighted.

Well, if I look at my plugins folder I have around 200 jar files.

Many of those do provide more than one plugin, which puts it way above 200 plugins.

The approach one process per plugin won't scale in such cases.

The lack of IPC performance for heavy communication, like it happens with plugins, is the main reason why microkernel based OS are yet to become mainstream.

Are all of those plugins active all the time? I doubt it.

This discussion is getting a little off track.

I'm simply saying that dismissing Go for not supporting plugins is rather illogical, as there are a lot of use cases that have no need of plugins. Servers being a good example of one of these use cases.

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