Summary:
We had somewhat inconsistent behaviour in multiplexed blobstore:
1) If on_put handlers are too slow (i.e. they are slower than all blobstores) then we
succeed as soon as all blobstores were successful (regardless of the value of
minimum_successful_writes). It doesn't matter if on_put handlers fail or
succeed, we've already returned success to our user.
2) However if all writes to the queue quickly fail, then we return a failure
even if writes to all blobstore were successful.
#2 seems like a change in behaviour from an old diff D17421208 (9de1de2d8b), and not a
desirable one - if blobstore sync queue is unavailable and it responds with
failures quickly, then blobstore writes will always fail even if all blobstores
are healthy.
So this diff makes it so that we always succeed if all blobstore puts were
successful, regardless of success or failures of on_put handlers.
Reviewed By: liubov-dmitrieva
Differential Revision: D29985084
fbshipit-source-id: 64338d552be45a70d9b1d16dfbe7d10346ab539c
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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