Nethermind.RocksDbBindings

RocksDB bindings

C# bindings for RocksDB.

Async reads

GetAsync and MultiGetAsync follow the results and error handling of Get and MultiGet. Keys are copied during submission. Read options must not be mutated until completion; disposing the database, read options or snapshot defers their native release until outstanding reads finish.

byte[]? value = await db.GetAsync(key);
KeyValuePair<byte[], byte[]?>[] values = await db.MultiGetAsync(keys);

GetAsync<T> accepts the existing ISpanDeserializer<T> and deserializes directly from native memory without copying the value into a managed byte array. For struct deserializers, use GetAsync<T, TDeserializer> to avoid boxing:

int value = await db.GetAsync<int, Int32Deserializer>(key, default);

readonly struct Int32Deserializer : ISpanDeserializer<int>
{
    public int Deserialize(ReadOnlySpan<byte> buffer)
        => System.Buffers.Binary.BinaryPrimitives.ReadInt32LittleEndian(buffer);
}

Missing keys return default(T) without invoking the deserializer. Deserialization runs on a thread-pool thread; shared deserializers must support concurrent calls. The span is valid only during Deserialize. Single reads use pooled completions: consume each returned ValueTask once, or call AsTask() once to share the result.

The API is the same on every platform. Linux builds enable RocksDB's native coroutine reads using Folly and io_uring. Windows, macOS and filesystems without a read executor use RocksDB's synchronous fallback, which can block during submission. DbOptions.SetReadIoExecutorThreads configures the shared executor on supported builds. This API does not cancel submitted reads.

License

This project is licensed under the MIT license.

Parts of the managed API were originally derived from rocksdb-sharp, used under BSD-2-Clause, and have since been substantially rewritten.

The package also ships prebuilt RocksDB binaries, used under the Apache-2.0 option of RocksDB's dual Apache-2.0/GPL-2.0 license. Those binaries statically link LZ4, Snappy, Zstandard, and, on Linux, jemalloc, Folly and its dependencies.