Benchmarking rust compilation speedups and slowdowns from sccache and -Zthreads

Just a PSA from one rust developer to another: if you use sccache, take a moment to benchmark a clean build1 of your favorite or current project and verify whether or not having RUSTC_WRAPPER=sccache is doing you any favors.

I’ve been an sccache user almost from the very start, when the Mozilla team first introduced it in the rust discussions on GitHub maybe seven years back or so, probably because of my die-hard belief in the one-and-only ccache earned over long years of saving my considerable time and effort on C++ development projects (life pro-tip: git bisect on large C or C++ projects is a night-and-day difference with versus without ccache). At the same time, I was always painfully aware of just how little sccache actually cached compared to its C++ progenitor, and I was left feeling perpetually discontented ever since learning to query its hit rate stats with sccache -s (something I never needed to do for ccache).

But my blind belief in the value of build accelerators led me to complacency, and I confess that with sccache mostly chugging away without issue in the background, I kind of forgot that I had RUSTC_WRAPPER set at all. But I recently remembered it and in a bout of procrastination, decided to benchmark how much time sccache was actually saving me… and the results were decidedly not great.

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  1. sccache does not cache nor speed up incremental builds, and recent versions try to more or less bypass the caching pipeline altogether in an attempt to avoid slowing down incremental builds. 

Using build.rs to integrate rust applications with system libraries like a pro

I’m happy to announce the release of version 0.2 of the rsconf crate, with new support for informing Cargo about the presence of custom cfg keys and values (to work around a major change that has resulted in hundreds of warnings for many popular crates under 1.80 nightly).

rsconf itself is a newer crate that was born out of the need (in the fish-shell transition from C++ to rust) for a replacement for some work that’s traditionally been relegated to the build system (e.g. CMake or autoconf) in order to “feature detect” various native system capabilities in the kernel, selected runtime (e.g. libc), or installed libraries. It (optionally) integrates with the popular cc crate so you can test and configure the build toolchain for various underlying features or behavior, and then unlock conditional compilation of native rust code that interops with the system or external libraries accordingly.

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tcpproxy 0.4 released

Image courtesy of Hack A Day

This blog post was a bit delayed in the pipeline, but a new release of tcproxy, our educational async (tokio) rust command line proxy project, is now available for download (precompiled binaries or install via cargo).

I was actually surprised to find that we haven’t written about tcpproxy before (you can see our other rust-related posts here), but it’s a command line tcp proxy “server” written with two purposes in mind: a) serving as a real-world example of an async (tokio-based) rust networking project, and b) serving as a minimal but-still-useful tcp proxy you can run and use directly from the command line, without needing complex installation or configuration procedures. (You can think of it as being like Minix, but for rust and async networking.)

The tcpproxy project has been around for quite some time, originally published in 2017 before rust’s async support was even stabilized. At the time, it manually chained futures to achieve scalability without relying on the thread-per-connection model – but today its codebase is a lot easier to follow and understand thanks to rust’s first-class async/await support.

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Implementing truly safe semaphores in rust

Discuss this article on r/rust or on Hacker News.

Low-level or systems programming languages generally strive to provide libraries and interfaces that enable developers, boost productivity, enhance safety, provide resistance to misuse, and more — all while trying to reduce the runtime cost of such initiatives. Strong type systems turn runtime safety/sanity checks into compile-time errors, optimizing compilers try to reduce an enforced sequence of api calls into a single instruction, and library developers think up of clever hacks to even completely erase any trace of an abstraction from the resulting binaries. And as anyone that’s familiar with them can tell you, the rust programming language and its developers/community have truly embraced this ethos of zero-cost abstractions, perhaps more so than any others.

I’m not going to go into detail about what the rust language and standard library do to enable zero-cost abstractions or spend a lot of time going over some of the many examples of zero-cost interfaces available to rust programmers, though I’ll just quickly mention a few of my favorites: iterators and all the methods the Iterator trait exposes have to be at the top of every list given the amount of black magic voodoo the compiler has to do to turn these into their loop-based equivalents, zero-sized types make developing embedded firmware in rust a dream and it’s really crazy to see how all the various peripheral abstractions can be completely erased giving you small firmware blobs despite all the safety abstractions, and no list is complete the newest member of the team, async/await and how rust manages to turn an entire web server api into a single state machine and event loop. (And to think this can be used even on embedded without a relatively heavy async framework like tokio and with even zero allocations to boot!)

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SecureStore 0.100: KISS, git-versioned secrets management for rust

A few days ago, we published a new version of both the securestore library/crate and the ssclient CLI used to create, manage, and retrieve secrets from SecureStore vaults, an open and cross-language protocol for KISS secrets management. SecureStore vaults provide a more secure and far more reliable solution to storing secrets in environment variables and a simpler and less error prone alternative to network-based secrets management solutions, and make setting up development environments a breeze.

For some background, the SecureStore protocol (first published in 2017) is an open specification and cross-language library/frontend for securely storing encrypted secrets versioned in git, alongside your code. We have implementations available in rust (crate, cli) and for C#/.NET (api and cli, nuget) and the specification is purposely designed to be both easy-to-use and easy-to-port to other languages or frameworks.

This is the first update with (minor) breaking changes to the securestore public api, although pains have been taken to ensure that most common workflows won’t break. The changes are primarily to improve ergonomics when retrieving secrets from rust, and come with completely rewritten docs and READMEs (for the project, the lib, and the cli).

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PrettySize 0.3 release and a weakness in rust’s type system

PrettySizeI’m happy to announce that a new version of size, the PrettySize.NET port for rust, has been released and includes a number of highly requested features and improvements.

The last major release of the size crate was 0.1.2, released in December of 2018. It was feature complete with regards to its original purpose: the (automatic) textual formatting of file sizes for human-readable printing/display purposes. It would automatically take a file size, pick the appropriate unit (KB, MB, GB, etc) to display the final result in, and choose a suitable precision for the floating numeric component. It had support for both base-10 (KB, MB, GB, etc) and base-2 (KiB, MiB, GiB, etc) types, and the user could choose between them as well as override how the unit was formatted. In short, it did one thing and did it right.

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Using SIMD acceleration in rust to create the world’s fastest tac

NeoSmart Technologies’ open source (MIT-licensed), cross-platform tac (written in rust) has been updated to version 2.0 (GitHub link). This is a major release with enormous performance improvements under-the-hood, primarily featuring handwritten SIMD acceleration of the core logic that allows it to process input up to three times faster than its GNU Coreutils counterpart. (For those that aren’t familiar with it, tac is a command-line utility to reverse the contents of a file.)

This release has been a long time in the making. I had the initial idea of utilizing vectorized instructions to speed up the core line ending search logic during the initial development of tac in 2017, but was put off by the complete lack of stabilized SIMD support in rust at the time. In 2019, after attempting to process a few log files – each of which were over 100 GiB – I decided to revisit the subject and implemented a proof-of-concept shortly thereafter… and that’s when things stalled for a number of reasons.

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Scripting in rust with self-interpreting source code

I have a soft spot in my heart for rust and a passionate distrust (that has slowly turned into hatred) for interpreted, loosely typed languages, but it’s hard to deny the convenience of being able to bang out a bash script you can literally just write and run without having to deal with the edit-compile-run loop, let alone create a new project, worry about whether or not you’re going to check it into version control, and everything else that somehow tends to go hand-in-hand with modern strongly typed languages.

A nifty but scarcely known rust feature is that the language parser will ignore a shebang at the start of the source code file, meaning you can install an interpreter that will compile and run your rust code when you execute the .rs file – without losing the ability to compile it normally. cargo-script is one such interpreter, meaning you can cargo install cargo-script then execute your source code (after making it executable, :! chmod +x %) with something like this:

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SecureStore: the open secrets container format

It’s been a while since we first released our SecureStore.NET library for C# and ASP.NET developers back in 2017, as a solution for developers looking for an uncomplicated way of safely and securely storing secrets without needing to build and maintain an entire infrastructure catering to that end. Originally built way back in 2015 to support secrets storage in legacy ASP.NET applications, SecureStore.NET has been since updated for ASP.NET Core and UWP desktop application development, and now we’re proud to announce the release of SecureStore 1.0 with multi-platform and cross-framework support, with an updated schema making a few more features possible and official implementations in C#/.NET and Rust.

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ignore-result: A simple crate to make ignoring rust Results safe and easy

Rust, both by design and by convention, has a fairly strongly defined model for strict error handling, designed to force developers to deal with errors up front rather than assume they don’t exist. If you stick to a few conventions and principles for best practice, error handling becomes fairly straight-forward (although what you ultimately do with the errors is a different question) if you are living in an all-rust world. The problems start when you step foot outside of the comfortable world of crates and Results, such as when dealing with FFI to interface with C libraries or using rust in an embedded context.

The typical approach for dealing with errors in rust in 2018 is to have any function that can encounter a scenario wherein it is unable to return a valid value declare a return type of Result<T, E> where T is the expected result type in normal cases and E is a type covering possible errors that can arise during execution. When calling from one such function into other functions with non-guaranteed success, the typical control flow in the event of an error is almost always “early out”:

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