Summary:
The `FileMetaData` objects associated with table files already contain the
number of the oldest blob file referenced by the SST in question. This patch
adds the inverse mapping to `BlobFileMetaData`, namely the set of table file
numbers for which the oldest blob file link points to the given blob file (these
are referred to as *linked SSTs*). This mapping will be used by the GC logic.
Implementation-wise, the patch builds on the `BlobFileMetaDataDelta`
functionality introduced in https://github.com/facebook/rocksdb/pull/6835: newly linked/unlinked SSTs are
accumulated in `BlobFileMetaDataDelta`, and the changes to the linked SST set
are applied in one shot when the new `Version` is saved. The patch also reworks
the blob file related consistency checks in `VersionBuilder` so they validate the
consistency of the forward table file -> blob file links and the backward blob file ->
table file links for blob files that are part of the `Version`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6945
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D21912228
Pulled By: ltamasi
fbshipit-source-id: c5bc7acf6e729a8fccbb12672dd5cd00f6f000f8
Summary:
The patch makes a couple of small cleanups to `SharedBlobFileMetaData` and `BlobFileMetaData`:
* It makes the constructors private and introduces factory methods to ensure these objects are always owned by `shared_ptr`s. Note that `SharedBlobFileMetaData` has an additional factory that takes a deleter object; we can utilize this to e.g. notify `VersionSet` when a blob file becomes obsolete (which is exactly when `SharedBlobFileMetaData` is destroyed).
* It disables move operations explicitly instead of relying on them being suppressed because of a user-declared destructor.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6749
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D21206947
Pulled By: ltamasi
fbshipit-source-id: 9094c14cc335b3e226f883e5a0df4f87a5cdeb95
Summary:
The patch adds a couple of classes to represent metadata about
blob files: `SharedBlobFileMetaData` contains the information elements
that are immutable (once the blob file is closed), e.g. blob file number,
total number and size of blob files, checksum method/value, while
`BlobFileMetaData` contains attributes that can vary across versions like
the amount of garbage in the file. There is a single `SharedBlobFileMetaData`
for each blob file, which is jointly owned by the `BlobFileMetaData` objects
that point to it; `BlobFileMetaData` objects, in turn, are owned by `Version`s
and can also be shared if the (immutable _and_ mutable) state of the blob file
is the same in two versions.
In addition, the patch adds the blob file metadata to `VersionStorageInfo`, and extends
`VersionBuilder` so that it can apply blob file related `VersionEdit`s (i.e. those
containing `BlobFileAddition`s and/or `BlobFileGarbage`), and save blob file metadata
to a new `VersionStorageInfo`. Consistency checks are also extended to ensure
that table files point to blob files that are part of the `Version`, and that all blob files
that are part of any given `Version` have at least some _non_-garbage data in them.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6597
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D20656803
Pulled By: ltamasi
fbshipit-source-id: f1f74d135045b3b42d0146f03ee576ef0a4bfd80
