| Age | Commit message (Collapse) | Author |
|---|
|
As preparatory step for extending the types of repositories that
are targeted by a just-mr fetch subcommand, names of certain
variables and of the currently only fetch operation async map were
changed to clarify that they only target archives.
|
|
|
|
|
|
|
|
To avoid unnecessary work, just-mr uses on-disk caches, including
for the mapping of a distdir to the corresponding git tree. This,
however, implies that the number of repositories that are actually
considered varies: in order to fetch a distdir repository, all
involved archives have to be fetched, but if we have a cache hit
none of them is even looked at.
So, in order to have a consistent reporting only count top-level
targets (i.e., the reachable repositories) in the statistics,
not the archives implicitly contained in a distdir, nor low-level
sub tasks. The actual fetch acitvity is shown separately by the
task tracker.
|
|
The improved GC implementation uses refactored storage
classes instead of directly accessing "unknown" file paths.
The required storage class refactoring is quite substantial
and outlined in the following paragraphs.
The module `buildtool/file_system` was extended by:
- `ObjectCAS`: a plain CAS implementation for
reading/writing blobs and computing digests for a given
`ObjectType`. Depending on that type, files written to the
file system may have different properties (e.g., the x-bit
set) or the digest may be computed differently (e.g., tree
digests in non-compatible mode).
A new module `buildtool/storage` was introduced containing:
- `LocalCAS`: provides a common interface for the "logical
CAS", which internally combines three `ObjectCAS`s, one
for each `ObjectType` (file, executable, tree).
- `LocalAC`: implements the action cache, which needs the
`LocalCAS` for storing cache values.
- `TargetCache`: implements the high-level target cache,
which also needs the `LocalCAS` for storing cache values.
- `LocalStorage`: combines the storage classes `LocalCAS`,
`LocalAC`, and `TargetCache`. Those are initialized with
settings from `StorageConfig`, such as the build root base
path or number of generations for the garbage collector.
`LocalStorage` is templated with a Boolean parameter
`kDoGlobalUplink`, which indicates that, on every
read/write access, the garbage collector should be used
for uplinking across all generations (global).
- `GarbageCollector`: responsible for garbage collection and
the global uplinking across all generations. To do so, it
employs instances of `LocalStorage` with `kDoGlobalUplink`
set to false, in order to avoid endless recursion. The
actual (local) uplinking within two single generations is
performed by the corresponding storage class (e.g.,
`TargetCache` implements uplinking of target cache entries
between two target cache generations etc.). Thereby, the
actual knowledge how data should be uplinked is
implemented by the instance that is responsible for
creating the data in the first place.
|
|
Co-authored-by: Sascha Roloff <sascha.roloff@huawei.com>
|
|
|
|
Both, the python script as well as the compiled variant of just-mr
fetch try to overwrite already existing distfiles in the distdir.
While it is unclear if overwriting existing distfiles or not
copying to distdir if a file with that name already exists is the
better behaviour, we at least should not error out, as the compiled
just-mr currently does as it sets permission to 444 and hence cannot
overwrite later; fix this by addwing owner write permissions before
overwriting.
|
|
|
