Summary:
In the code base, "channel" is used to denote the OS mechanism that sends
EdenFS notifications. In macOS and Linux, that's Fuse, on Windows, that's
ProjectedFS. To avoid platform specific naming in ObjectedFetchContext, let's
rename the fetch cause enum.
Reviewed By: kmancini
Differential Revision: D23462460
fbshipit-source-id: 3ac68cdf4999e6a3b4ff4ee266f94e1f9736df39
Summary:
This commit introduces a new process spawning class derived
from the ChildProcess class in the watchman codebase.
`SpawnedProcess` is similar to folly::Subprocess but is designed around the
idea that we will use a system provided spawning API to start a process, rather
than assuming the use of `fork`.
`fork` is to be avoided because it can be expensive for processes with large
address spaces and also because it interacts poorly with threads on macOS. In
particular, we see the objC runtime terminating our process in some scenarios
where fork and threads are mixed.
There are some important differences from `folly::Subprocess` and that means
that some assumptions and uses need to be altered slightly from their prior
workings. For example, detaching a SpawnedProcess moves the responsibility of
waiting on the child to a periodic task as there is no way to detach via
posix_spawn without also using fork.
On the plus side, this commit allows unifying spawning between posix and
windows systems, which simplifies the code!
Reviewed By: xavierd
Differential Revision: D23287763
fbshipit-source-id: b662af1d7eaaa9ed445c42f6c5765ae9af975eea
Summary:
I'm not sure if that's the right thing to do, so I'd like feedback on that.
Check for opcode was added in D22050919 (fdb1af8bc9), but there was also a comment from
chadaustin
```
Why do you think fuseHeader isn't staying valid? It's a struct that's copied
into the RequestData. It does look like stealReq() sets the opcode to 0, but I
don't see anything that would affect the pid field.
```
So I wonder if this code can be responsible for some of the blind spots in
logging?
Reviewed By: chadaustin
Differential Revision: D23422635
fbshipit-source-id: 4d9a7171d685eb3f6f69da7b8a191df2f65ad897
Summary:
Setting up, tearing down, and querying RequestContext has some
overhead that I would like to avoid in the inner FUSE loop, so replace
RequestData with a single class that's heap-allocated at the start of
a request and is guaranteed to survive until the request ends, and is
otherwise explicitly passed where it's needed.
Reviewed By: kmancini
Differential Revision: D22712310
fbshipit-source-id: fc30d0b0f7e22b39306b857194ea07a913110b0f
Summary:
Our error handling looked pretty, but allocating all of these futures
is expensive. Each future is an allocation and some atomics. This diff
buys back some performance which I will soon spend on a new async
event queue.
Reviewed By: xavierd
Differential Revision: D22799737
fbshipit-source-id: 91dcfe974cf8f461109dfaa9dbf75c054ed84f59
Summary:
Avoid some overhead and complexity by storing BufVec as a
unique_ptr<IOBuf>. The complexity can be reintroduced if we ever find
FUSE splice support to be a performance win for us.
Reviewed By: kmancini
Differential Revision: D22710795
fbshipit-source-id: e58eedc0fb5cea9e9743ccd20d3e4e2b7cc5d198
Summary:
The tilde got dropped as part of the changes in D22672240 (be3683b1d4)
(an easy mistake to make!) and that renders this function less
useful.
Thankfully the caps display isn't a critical function; just for
some diagnostic printing.
Reviewed By: chadaustin
Differential Revision: D22847590
fbshipit-source-id: 716d7c7bd674260687fbc09e3dc94538359f98b3
Summary:
As opposed to FUSE, ProjectedFS sends notifications for file/directory creation
after the fact, and for directory that means these will be visible on disk before
EdenFS may be aware of it. While EdenFS usually process it quickly, a heavily
multi-threaded application that tries to concurrently create a directory
hierarchy may end up sending notifications to EdenFS in a somewhat out of order
fashion.
Since this should be a very rare occurence, we make this a very slow path by
being optimistic and calling `getInode` first, and then only if that fails, we
aggressively create all the parent directories. During a buck build of ~1k
jobs, this happened only 3 times.
If we fully think this through, this change doesn't fully fix the race, as a
similar race can now happen when a create and remove/rename operations are
concurrent. However, a client performing these operations concurrently is
either aware that this is racy and should handle these properly, or is most
likely buggy. Both of these should significantly reduce the likelyhod of this
happening, thus, I'm leaving this unfixed for now.
To better understand how frequently this happens, I've added a stat counter.
For now, these aren't published to ODS, but this will be tackled later.
Reviewed By: wez
Differential Revision: D22783484
fbshipit-source-id: ea3aafc2f77b65d3967f697f68114921d5909137
Summary:
To avoid mistakes when refactoring, static_assert that the template
variant of sendReply and make_iovec are only used with POD types.
Reviewed By: genevievehelsel
Differential Revision: D22710742
fbshipit-source-id: 4557761f3946fe8969ce31a42502f64cc3298e1d
Summary:
Previously, we kept a list of weak pointers to RequestData instances
to track live FUSE calls, but the only thing we need is the FUSE
request header, so directly track that instead.
Reviewed By: kmancini
Differential Revision: D22710716
fbshipit-source-id: 3820acb314ac2db85b86de128fd082bc4871d9c6
Summary:
Now that we are explicit about whether the kernel caches must be
invalidated, we can remove a use of folly::RequestContext.
Reviewed By: kmancini
Differential Revision: D22710518
fbshipit-source-id: 4bd5267bf5dd3135adf33e4f4fa1ea2649816564
Summary:
Avoid the cost of dynamically querying whether we are in a FUSE
request handler or not by passing a flag.
Reviewed By: genevievehelsel
Differential Revision: D22710397
fbshipit-source-id: 7c62f45dfc227416c91070842a349b9d0c626cba
Summary:
We're experimenting with enabling NO_OPEN support in our internal
build of the osxfuse kext. This commit includes the relevant capability bits
for the kernel interface (which are compatible with the linux FUSE
implementation) as well as adjusts our FUSE client code to detect and use
those bits on macOS.
Reviewed By: xavierd
Differential Revision: D22744378
fbshipit-source-id: 21376439a85b0b0f5a71916dd1af618d9627695e
Summary:
check fetch count before `getPriority()` is used. If fetch count has exceeded `fetchThreshold_`, lower the priority by 1.
Note: this diff only guarantees that the `getPriority()` function is returning the lowered priority. How the returned value is used for scheduling is handled by `HgQueuedBackingStore`
Reviewed By: kmancini
Differential Revision: D22550640
fbshipit-source-id: c032f8f72ca658618ac118dfb3ad3dcae61e9735
Summary: Previously `getPriority()` always returned a fixed priority. Now that we want `ObjectFetchContext` to lower its priority, it is better to make it have its own copy of `ImportPriority`.
Reviewed By: kmancini
Differential Revision: D22550587
fbshipit-source-id: 029c797def477ae4533f66cfba146a3972cfb65d
Summary:
This is much better than having `ObjectFetchContext` itself owns a copy of `ImportPriority`. We can actually customize how different fetch context manages these priority.
We set all FUSE requests to a higher priority and prefetch requests to a lower priority
Reviewed By: xavierd
Differential Revision: D22342802
fbshipit-source-id: b9c1d0f2ddbc7a5e5d619bc2c2222e5df0e702af
Summary: This commit makes `readdir()` to correct send its `RequestContext` to `EdenDispatcher` method so underlying code can know the current request being processed is from FUSE.
Reviewed By: xavierd
Differential Revision: D21821949
fbshipit-source-id: f41ba912fedbfc040e3c9267aad25e7f33f8e912
Summary:
Recently the server team added an un-used directory to test that eden would not
fetch these as a test for the upcoming repo merge. They saw that these files
were fetched a non trivial number of times. We want to know why eden is causing
these fetches.
This adds the pid and interface through which the client is interacting with eden to
ObjectFetchContext for this purpose. This information will be logged in later
changes.
note: currently this is only for fetches through Fuse (thrift interface to follow).
Reviewed By: chadaustin
Differential Revision: D22050919
fbshipit-source-id: 49b93257a0e6d910f48b1e8ec6471527e056d22a
Summary:
In following changes I will be threading ObjectFetchContext into the backing
store importing process, since this will start to be used more outside of the
ObjectStore, I am moving this class into its own files.
Reviewed By: chadaustin
Differential Revision: D22022488
fbshipit-source-id: 1a291fea6e0fd56855936962363dfc9f6de8533d
Summary: This diff adds a PID-fetchCounts map to `ObjectStore` and makes `ObjectStore` update that map after every `didFetch`
Reviewed By: kmancini
Differential Revision: D22100413
fbshipit-source-id: 740342c7b4a453fe482344c2db9542381c3772e4
Summary:
This diff makes `lookup` to use `RequestData` as `ObjectFetchContext` in `getattr` calls.
This will make sure we correctly record backing store fetches in `eden top`
Reviewed By: chadaustin
Differential Revision: D21780969
fbshipit-source-id: 468e2fadcebf4a00477bc5de434e6c658b99d1ce
Summary: This diff starts to use `RequestData` as `ObjectFetchContext` in our `read()` methods. This ensures EdenFS could track backing store fetches happened in FUSE requests.
Reviewed By: chadaustin
Differential Revision: D21792503
fbshipit-source-id: 9509a1bc8f28100a0dfe196e312c4785c7842345
Summary:
Previously we check if a request is a fuse request when we fetch anything from backing store, so we can collect number of fetches happened for each process in eden top.
This is creating a dependency from store to fuse, which is a little awkward. Instead, we could make `RequestData` a `ObjectFetchContext` and record the fetches when that happens.
Similarly in the future we should also have something equivalent in our Thrift layer.
Reviewed By: kmancini
Differential Revision: D21775919
fbshipit-source-id: 95056830ddbe7c999051c43e0d8eca9a67350904
Summary: Fix some RVO warnings and a compilation error when compiling with gcc.
Reviewed By: xavierd
Differential Revision: D21481738
fbshipit-source-id: 0621f5886df40c24ef1a6a68ccd957e38f2f4122
Summary: EdenFS doesnt daemonize correctly due to the privhelper not closing fd 0 (see http://www.faqs.org/faqs/unix-faq/programmer/faq/). This redirects stdin to /dev/null/ in order to do so.
Reviewed By: xavierd
Differential Revision: D21602545
fbshipit-source-id: 0aeb589efbf214ef22c0db039fbb6a436a71e360
Summary:
In glibc, pthread cancellation support adds two atomic CAS operations
to each "cancellation point" syscall (see pthreads(7)). This includes
read() and write(). We can avoid that overhead by disabling pthread
cancellation at the start of the FUSE worker threads.
This saves two CAS operations (~40 ns) in the critical FUSE request
processing loop.
Reviewed By: simpkins
Differential Revision: D21469690
fbshipit-source-id: 7f28a2a8e831006351657981e901dc572c58cf48
Summary:
See the comment in FuseChannel.cpp, but it's currently not easy to
avoid the "security.capability" getxattr request for every
write. Since we can't avoid the request, the fastest thing we can do
is branch, strcmp, and fast-path a result on the same thread.
This appears to save three or four microseconds in the 4k random write
benchmark.
Reviewed By: wez
Differential Revision: D21341973
fbshipit-source-id: a23620767f4bdec4daf02ecfe3acb924dd57857a
Summary: These third-party includes are edenfs-specific, so move them into eden/fs/
Reviewed By: simpkins
Differential Revision: D21314642
fbshipit-source-id: c52b0a00d5080934e1f07e4cd55373602f2f6b0a
Summary:
While EdenFS does not use a separate privhelper process on Windows, it still
defines a stub PrivHelper class. However, this class was previously defined
in a separate win/utils/Stub.h header file, which led to awkward `#ifdef`s to
include the correct platform-specific header file.
This diff moves the definition of the dummy PrivHelper class in Windows into
the same `PrivHelper.h` header file used on POSIX platforms. This results in
a few more `ifdef`s in the PrivHelper files, but fewer `ifdef`s in the calling
code, and will make it easier to start unifying more of the `EdenMain` logic
on Windows and non-Windows platforms.
Reviewed By: xavierd
Differential Revision: D21332568
fbshipit-source-id: c63bf2b4a8b7e767d7db7dcda28675f735c23bf8
Summary:
The kernel has some legacy logic to attempt to clear the setuid and
setgid mode bits upon writes, but it is racy and disabled by default
in libfuse3. Now that we don't support setgid and setuid bits at all,
opt out of the legacy kernel behavior.
Reviewed By: wez
Differential Revision: D21334075
fbshipit-source-id: bdef12c1958a5e9bd2649c2bcb54975b0b4e78d6
Summary:
Instead of multiple linear array scans to determine the type of a FUSE
request, use a single lookup table. This is a small optimization, but
it makes the code a bit nicer too.
Reviewed By: wez
Differential Revision: D21314720
fbshipit-source-id: 5b6700ad5bb8e353da1e457de1533e6a626e8f68
Summary:
Move the `UserInfo` code from `fuse/privhelper` to `utils`, and also unify the
POSIX and Windows implementations of this class.
This code was originally put in the `fuse/privhelper` directory since it was
written at the same time as the privhelper. However, it's really a
lower-level library that doesn't depend on FUSE or any of the other code in
the `fuse/` subdirectory.
Reviewed By: wez
Differential Revision: D21296594
fbshipit-source-id: f58682f6ce86bba0328472c491bb4c0dc3370319
Summary:
Tl;DR Reduces costs of fuse request mertics by reducing lock contention.
D20922194 adds tracking for FUSE request metrics, this makes tracking those
metrics more efficient. Since every user request goes through the FUSE channel,
we want to reduce the cost of these metrics as much as possible (originally
mentioned in a comment D20922194).
The synchronization used to track the metrics is costly especially
when the lock is contended.
To reduce the cost, each FuseChannel will have a thread local copy of metrics.
Each will still be synchronized to allow for reading the metrics and for
Requests moved to other threads that will need to access the metrics. However,
the lock should be contended less often since only requests from a single fuse
channel thread will access it.
Reviewed By: chadaustin
Differential Revision: D21043792
fbshipit-source-id: ce58a0cbce334095976233bfac7578d39c81bb55
Summary:
This exposes metrics for the live FUSE requests (the duration
of the longest outstanding request and the number of outstanding
requests).
Because FUSE is the interface through which the user mostly interacts
with the file system they provide good metrics to judge if the perfomance
of eden is normal, or there may be an issue.
Exposing these counters this way will send them to ods, so it will not only
allow for debuging current issues, but can be used to look back at previous
problems. This data could also be used for alerting or more proactive
remediation.
Metrics are exposed per checkout to allow seeing which checkout was
having issues. This data will aggregated in `eden top` to be used as
an overall health indicator, but should more information be needed it
will be logged in ods.
Reviewed By: chadaustin
Differential Revision: D20922194
fbshipit-source-id: 16208883417acb77b62bf712cfdd9068c5420303
Summary:
Build and run the fuse privhelper unit tests, as well as the `drop_privs`
helper program used by some of the integration tests.
Reviewed By: wez
Differential Revision: D21004425
fbshipit-source-id: 650e0729909f4753095e19fba4f01c02d516713b
Summary:
The `eden_fuse_privhelper` library depends on CoreFoundation and IOKit.
Previously this dependency was specified for the `eden_service` library, which
doesn't use these frameworks directly, only indirectly through the
`eden_fuse_privhelper` library.
The fact that `eden_fuse_privhelper` was missing this dependency causes
problems when trying to build unit tests and tools that depend on
`eden_fuse_privhelper` without using the `eden_service` library.
Reviewed By: genevievehelsel
Differential Revision: D21057925
fbshipit-source-id: b846ebde0de158b70be462067c4412a655ad8036
Summary:
D20846826 added a dependency from the fuse library to the telemetry code,
so the CMakeLists.txt file needs to be updated.
Reviewed By: genevievehelsel
Differential Revision: D21083715
fbshipit-source-id: 823cc2eb128808d0e807c6b91cacc9fd91cdad48
Summary:
This sets up the counters that will allow us to expose metrics for
live FUSE requests in Eden top.
This will allow us to track the number of live FUSE requests and the duration
of the longest FUSE request. If the duration of the longest FUSE request has
become very long, the number of FUSE requests is stuck at some value or
increasingly growing these can indicate there is a problem with the Fuse Channel
or something effecting this.
This provides more insight beyond the metrics for imports since many of the
FUSE requests will not cause imports, so this monitors more functionality.
Further because all user interaction with the filesystem goes through FUSE,
these metrics will give a good overall indication weather Eden is performing
normally.
Reviewed By: chadaustin
Differential Revision: D20846826
fbshipit-source-id: 34d834d193833a3c91d95fbb87361ddd863f64ca
Summary:
Some of our types were vulnerable to the issue described in
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1008r0.pdf so
make all deleted default constructors explicit.
Reviewed By: simpkins
Differential Revision: D21008976
fbshipit-source-id: 5b21923f25121dabf4bb0ea55f94536fb3532e6b
Summary:
The bind-mounts configuration has been ignored by EdenFS since D17236366.
This removes all CLI code for dealing with this config section.
Reviewed By: wez
Differential Revision: D20876460
fbshipit-source-id: 6b3f3552de25ee28fc0418a6aaec14446520203c
Summary:
Plumb the read-only mount flag into FUSE on macOS. This fixes a build
warning and enables the --read-only mount flag.
Reviewed By: wez
Differential Revision: D20634119
fbshipit-source-id: a5e68cd163e36ceb6d86fd753844718ee9a5727f
Summary:
Migration from Future-returning executor-erasing collectX forms to
SemiFuture-returning forms, that are less risky in particular with coroutines.
Earlier diffs added SemiFuture and Unsafe versions. This codemod migrates
collect versions to the Unsafe versions to allow the basic collect versions to
be made safe.
Reviewed By: simpkins
Differential Revision: D20331206
fbshipit-source-id: efc8dff487d45f7d53ee55e8c4696bd3eed0e6da
Summary:
Call `folly::setThreadName()` in the privhelper process when it starts. This
changes the command name reported in `/proc/PID/comm` and in `ps`
The process name is limited to 15 bytes, so this shows up as `edenfs_privhelp`
Reviewed By: fanzeyi
Differential Revision: D20199409
fbshipit-source-id: a5349bfab9230174aaa99c87f0db73fe31659186
Summary:
This commit causes a desktop notification to be shown if we generate
EIO or ETIMEDOUT responses via fuse; the prompt is intended to make it obvious
to the user that they need to connect to the VPN.
The commit by itself doesn't show a notification, it allows configuring a
command that can be run to do something to show a notification.
The test plan includes one such configuration for our corp environment.
* It doesn't trigger for thrift-originated downloads (eg: prefetch), only for
VFS operations through FUSE.
* Ideally we'd know exactly when we have a network related error in the store
code and use that to trigger the notification. However, we have a rather
convoluted set of importers and fallbacks today, one of which is interpreting
a generic response returned from a pipe, so it is not especially clear
exactly where we should locate the logic
Reviewed By: chadaustin
Differential Revision: D17513364
fbshipit-source-id: 45134f3672679cb5580cb0c1bc12a0d6e38525ca
