Summary:
This diff turns the return type of `BackingStore::getBlob` from `folly::Future` into `folly::SemiFuture` to prevent executor leaks.
This also enable us to remove the need of holding `serverThreadPool` from backing stores.
----
**Changes**
* `ObjectStore` now needs to hold a `folly::Executor::KeepAlive` that is used to turn `SemiFuture`s it gets from backing stores into `Future`.
* Signature changes of the implementations of `BackingStore` class.
* For tests, I chose to use `QueuedImmediateExecutor` in place of `UnboundedQueueExecutor` as it will basically execute tasks inline. I'm concerned introducing thread pool executor in tests may turn tests flaky.
Reviewed By: wez
Differential Revision: D18669664
fbshipit-source-id: 0cae89f365dcf8b345b49d64469a530cf25d4ac5
Summary: Adds a function which takes both the manifestID and the commitID to get a Tree. This will be used in `checkOutRevision()` and this allows us to skip looking up the manifestID since the caller can just pass it in themselves.
Reviewed By: wez
Differential Revision: D18719405
fbshipit-source-id: 919f0a7c84bff4a2f0bc20110c45bd272f9e9107
Summary:
Update the copyright & license headers in C++ files to reflect the
relicensing to GPLv2
Reviewed By: wez
Differential Revision: D15487078
fbshipit-source-id: 19f24c933a64ecad0d3a692d0f8d2a38b4194b1d
Summary:
Now that the import bug has been fixed for some time, it's likely few
people have cached empty files. And if they do, `eden gc; eden
restart` is a fine workaround.
On the other hand, reimporting empty files gums up the importer, and
I've seen several people recently complaining about performance that
could be partially attributed to the fact that their Eden needed to
verify empty files. simpkins has talked about adding a bit to the
cached blob to determine whether it needs reimporting or not, but it's
probably going to take a while for anyone to implement that, and this
reverification logic is hurting people today.
Reviewed By: strager
Differential Revision: D10456519
fbshipit-source-id: 657bc377ee16ce93494075bde4388aed59dceecf
Summary:
When we load an empty blob from the LocalStore double check with the
BackingStore to confirm that it should actually be empty.
We have seen multiple instances of files being incorrectly imported as empty.
So far this error has always been fixed by a re-import. We still haven't
tracked down the root cause, but this change should help workaround the issue
by ensuring that we double check the file contents before returning the data.
Reviewed By: chadaustin
Differential Revision: D9476522
fbshipit-source-id: 6d57cf15c42736ecbcb106a731259b77db06d8f1
Summary:
D8065370 changed the HgImporter code to make a blocking `get()` call on a
future from the hg importer thread pool. This caused deadlocks, since all of
the hg importer threads could become stuck waiting on these `get()` calls to
complete. These would be waiting on RocksDbLocalStore threads which were in
turn all busy waiting to schedule operations on the HgImporter threads.
This fixes the code to use `Future::then()` rather than `Future::get()` to
avoid blocking the HgImporter threads on these operations.
Reviewed By: wez
Differential Revision: D8438777
fbshipit-source-id: a0d647b10ef5a182be2d19f636c2dbc24eab1b23
Summary:
This removes the main point of contention for eden prefetch
in two ways:
1. We batch up the complete list of blobs so that they can be processed
in bulk rather than stalling the tree walk
2. We can ask remotefilelog to check and fetch that list to the local
hgcache, again as a batch, rather than by forcing the data to be
loaded through into the local store
The goal of this prefetch is to bulk load data from the mercurial server
so that a subsequent file access doesn't have to make a one-off ssh session
for each one, rather than making sure that all the data is loaded into
the local store.
Reviewed By: chadaustin
Differential Revision: D7965818
fbshipit-source-id: 753400460d633b5467c5110e3f5608ce06106e00
Summary:
Per discussion with bolinfest, this brings Eden in line with clang-format.
This diff was generated with `find . \( -iname '*.cpp' -o -iname '*.h' \) -exec bash -c "yes | arc lint {}" \;`
Reviewed By: bolinfest
Differential Revision: D6232695
fbshipit-source-id: d54942bf1c69b5b0dcd4df629f1f2d5538c9e28c
Summary:
Update copyright statements to "2016-present". This makes our updated lint
rules happy and complies with the recommended license header statement.
Reviewed By: wez, bolinfest
Differential Revision: D4433594
fbshipit-source-id: e9ecb1c1fc66e4ec49c1f046c6a98d425b13bc27
Summary:
Update the ObjectStore and BackingStore classes to have APIs that return
folly::Future objects, rather than blocking until the requested data is loaded.
For now most users still call the blocking versions of getBlob() and getTree().
Furthermore, all of the Future-based implementations actually still block
until the data is ready. I will update the code to use these new APIs in
future diffs, and then deprecate the non-future based versions.
Reviewed By: bolinfest
Differential Revision: D4318055
fbshipit-source-id: a250c23b418e69b597a4c6a95dbe80c56da5c53b
Summary:
This adds an HgBackingStore implementation which can load tree data from a
mercurial repository. Blob loading is not implemented yet, but will come in a
separate diff.
This also adds a minimal GitBackingStore class. The GitBackingStore has nearly
no functionality, but is needed to keep the existing git functionality working.
Reviewed By: bolinfest
Differential Revision: D3409743
fbshipit-source-id: dbebf53e9de08bd1469e489baa48b84cbf889511
Summary:
Add the basic BackingStore interface, plus a NullBackingStore implementation
that always returns null. This updates the ObjectStore to query the
BackingStore if data is not found in the LocalStore.
Additionally, this updates EdenServer to manage the BackingStore objects. It
maintains a map of the BackingStore objects created for each known repository.
Reviewed By: bolinfest
Differential Revision: D3409602
fbshipit-source-id: 2920dc4c24ee1ec37efb542f058d0d121ceb5532
