Summary:
This adds support for periodically logging that a command is in progress in
Mononoke. The underlying motivation is to make sure that if something is taking
a long time, we can still show some feedback to the user (and log to Scuba). We
might want to log this every 30 seconds.
That said, this is more of an RFC at this stage. I'm thinking it might make
sense to log to Scuba more often and to users less often. It might make sense
to also restrict this to specific commands, such as unbundle:
https://fburl.com/scuba/mononoke_test_perf/atik5959
Reviewed By: StanislavGlebik
Differential Revision: D21549862
fbshipit-source-id: 1d02c5c926abc7e491ac5b8ae0244b5f4620c93e
Summary:
Advertise support for `b2x:infinitepushmutation`. When the client sends us
mutation information, store it in the mutation store.
Reviewed By: mitrandir77
Differential Revision: D20871340
fbshipit-source-id: ab0b3a20f43a7d97b3c51dcc10035bf7115579af
Summary:
Limits on concurrent calls are a bit hard to reason about, and it's not super
obvious what a good limit when all our underlying limits are expressed in QPS
(and when our data sets don't have peak concurrency - instead they have
completion time + # blob accesses).
Considering our past experience with ThrottledBlob has been quite positive
overall, I'd like to just use the same approach in ContextConcurrencyBlobstore.
To be safe, I've also updated this to be driven by tunables, which make it
easier to rollout and rollback.
Note that I removed `Debug` on `CoreContext` as part of this because it wasn't
used anywhere. We can bring back a meaningful implementation of `Debug` there
in the future if we want to. That triggered some warnings about unused fields,
which for now I just silenced.
Reviewed By: farnz
Differential Revision: D21449405
fbshipit-source-id: 5ca843694607888653a75067a4396b36e572f070
Summary:
When we log to Scuba, we need to truncate the `msg` field if it's too long, or
we might be missing log entries in Scuba. I put this behind a tunable so we can, well,
tune it.
Reviewed By: farnz
Differential Revision: D21405959
fbshipit-source-id: 08f0d3491d1a9728b0ca9221436dee2e8f1a17eb
Summary: Let's make it tunable, more context in D21300885
Reviewed By: ikostia, krallin
Differential Revision: D21347636
fbshipit-source-id: 4bc91effdd212a3f5c4a0c3d4952f52a1cf417d7
Summary:
Currently, Mononoke's configs are loaded at startup and only refreshed
during restart. There are some exceptions to this, including throttling limits.
Other Mononoke services (such as the LFS server) have their own implementations
of hot reloadable configs, however there isn't a universally agreed upon method.
Static configs makes it hard to roll out features gradually and safely. If a
bad config option is enabled, it can't be rectified until the entire tier is
restarted. However, Mononoke's code is structured with static configs in mind
and doesn't support hot reloading. Changing this would require a lot of work
(imagine trying to swap out blobstore configs during run time) and wouldn't
necessarily provide much benefit.
Instead, add a subset of hot reloadable configs called tunables. Tunables are
accessible from anywhere in the code and are cheap to read as they only require
reading an atomic value. This means that they can be used even in hot code
paths.
Currently tunables support reloading boolean values and i64s. In the future,
I'd like to expand tunables to include more functionality, such as a rollout
percentage.
The `--tunables-config` flag points to a configerator spec that exports a
Tunables thrift struct. This allows differents tiers and Mononoke services to
have their own tunables. If this isn't provided, `MononokeTunables::default()`
will be used.
This diff adds a proc_macro that will generate the relevant `get` and `update`
methods for the fields added to a struct which derives `Tunables`. This struct is
then stored in a `once_cell` and can be accessed using `tunables::tunables()`.
To add a new tunable, add a field to the `MononokeTunables` struct that is of
type `AtomicBool` or `AtomicI64`. Update the relevant tunables configerator
config to include your new field, with the exact same name.
Removing a tunable from `MononokeTunables` is fine, as is removing a tunable
from configerator.
If the `--tunables-config` path isn't passed, then a default tunables config
located at `scm/mononoke/tunables/default` will be loaded. There is also the
`--disable-tunables` flag that won't load anything from configerator, it
will instead use the `Tunable` struct's `default()` method to initialise it.
This is useful in integration tests.
Reviewed By: StanislavGlebik
Differential Revision: D21177252
fbshipit-source-id: 02a93c1ceee99066019b23d81ea308e4c565d371
