Summary:
Before this diff, we did DNS lookups using a crate called `dns_lookup`. This crate is a thin layer over libc DNS lookups. Those lookups are blocking (i.e. they hold a thread), so they're not very friendly to asynchronous code. We currently offload them on a dedicated thread pool to mitigate the issue, but this isn't ideal: if we experience e.g. slow DNS responses, we could saturate this thread pool pretty easily.
I updated it to use the trust-dns crate, which provides an asynchronous implementation of DNS lookups, and is currently used in other parts of Mononoke.
Reviewed By: krallin
Differential Revision: D25849872
fbshipit-source-id: 826ab4e5618844f3b48e5def4ad9bd163753ebb1
Mononoke is a next-generation server for the Mercurial source control
system, meant to scale up to accepting
thousands of commits every hour across millions of files. It is primarily
written in the Rust programming language.
Caveat Emptor
Mononoke is still in early stages of development. We are making it available now because we plan to
start making references to it from our other open source projects.
The version that we provide on GitHub does not build yet.
This is because the code is exported verbatim from an internal repository at Facebook, and
not all of the scaffolding from our internal repository can be easily extracted. The key areas
where we need to shore things up are:
Full support for a standard cargo build.
Open source replacements for Facebook-internal services (blob store, logging etc).
The current goal is to get Mononoke working on Linux. Other Unix-like OSes may
be supported in the future
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