3 releases
0.1.16-alpha.0 | Mar 31, 2023 |
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0.1.12-alpha.0 | Jan 19, 2023 |
0.1.10-alpha.0 | Jan 18, 2023 |
#39 in #leveldb
308 downloads per month
Used in 69 crates
(via bitcoinleveldb-db)
1.5MB
3.5K
SLoC
bitcoinleveldb-version Crate Description
Short Description
bitcoinleveldb-version
is a Rust crate that is
a direct translation from C++ to Rust of the
bitcoin core. It contains various structs and
functions related to version management in the
leveldb database.
Version Management in Leveldb
Leveldb uses version management to keep track of multiple versions of the database, each representing a specific point in time. This allows for efficient read and write operations and helps maintain consistency.
The Version
struct represents a specific version
of the database, while the VersionSet
struct
keeps track of all the versions.
The VersionSetBuilder
struct is used to build
a new VersionSet
by adding and removing files,
creating new levels, and performing compactions.
The Compaction
struct represents a compaction
operation that merges multiple versions into a new
version, while the ManualCompaction
struct is
used to manually control the compaction process.
Notice
This crate is part of a direct translation from C++ to Rust of the bitcoin core. As such, some of the function bodies may still be in the process of translation. Please note that this system will become testable once the translation process is complete.
89> could you describe version management in the context of leveldb in more detail?
Certainly! In LevelDB, version management is crucial to ensuring the consistency and correctness of the database. Each version represents a snapshot of the database at a given point in time, and contains information about the file set and their corresponding metadata (e.g. file sizes, index block handles, etc.). The version management system allows for efficient querying of the database and provides the foundation for read and write operations.
At a high level, the version management system in
LevelDB consists of a number of components,
including the Version
, VersionEdit
,
VersionSet
, and VersionSetBuilder
.
-
Version
represents a snapshot of the database at a given point in time, and contains information about the file set and their corresponding metadata. EachVersion
contains a list of levels, where each level consists of a set of files with non-overlapping key ranges. -
VersionEdit
is a mutable counterpart toVersion
, and is used to modify the file set of aVersion
. When a modification is made to aVersion
, it is represented as a sequence ofVersionEdit
objects. -
VersionSet
manages a set ofVersion
objects, and provides the foundation for read and write operations.VersionSet
provides an interface for reading and querying the database, and also manages the set of activeVersion
objects. -
VersionSetBuilder
is used to build a newVersion
object based on a sequence ofVersionEdit
objects. It maintains an in-memory representation of the current file set and its metadata, and updates it in response toVersionEdit
objects. Once allVersionEdit
objects have been applied,VersionSetBuilder
constructs a newVersion
object from the updated file set and its metadata.
In summary, the version management system in LevelDB is responsible for maintaining the consistency and correctness of the database by providing efficient querying, read and write operations, and snapshotting functionality. It is a critical component of the database, and must be carefully designed and implemented to ensure that it meets the performance and reliability requirements of the application.
Dependencies
~89MB
~855K SLoC