Commit Graph

5 Commits

Author SHA1 Message Date
Gang Liao 056e08d6c4 Enable blob caching for MultiGetBlob in RocksDB (#10272)
Summary:
- [x] Enabled blob caching for MultiGetBlob in RocksDB
- [x] Refactored MultiGetBlob logic and interface in RocksDB
- [x] Cleaned up Version::MultiGetBlob() and moved 'blob'-related code snippets into BlobSource
- [x] Add End-to-end test cases in db_blob_basic_test and also add unit tests in blob_source_test

This task is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10272

Reviewed By: ltamasi

Differential Revision: D37558112

Pulled By: gangliao

fbshipit-source-id: a73a6a94ffdee0024d5b2a39e6d1c1a7d38664db
2022-06-30 13:24:35 -07:00
Gang Liao d7ebb58cb5 Add blob cache tickers, perf context statistics, and DB properties (#10203)
Summary:
In order to be able to monitor the performance of the new blob cache, we made the follow changes:
- Add blob cache hit/miss/insertion tickers (see https://github.com/facebook/rocksdb/wiki/Statistics)
- Extend the perf context similarly (see https://github.com/facebook/rocksdb/wiki/Perf-Context-and-IO-Stats-Context)
- Implement new DB properties (see e.g. https://github.com/facebook/rocksdb/blob/main/include/rocksdb/db.h#L1042-L1051) that expose the capacity and current usage of the blob cache.

This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10203

Reviewed By: ltamasi

Differential Revision: D37478658

Pulled By: gangliao

fbshipit-source-id: d8ee3f41d47315ef725e4551226330b4b6832e40
2022-06-28 13:52:35 -07:00
Gang Liao a1eb02f089 Change the semantics of bytes_read in GetBlob/MultiGetBlob for consistency (#10248)
Summary:
The `bytes_read` returned by the current BlobSource interface is ambiguous. The uncompressed blob size is returned if the cache hits. The size of the blob read from disk, presumably the compressed version, is returned if the cache misses. Two differing semantics might cause ambiguity and consistency issues. For example, this inconsistency causes the assertion failure (T124246362 and its hot fix is https://github.com/facebook/rocksdb/issues/10249).

This goal is to require that the value of `byte read` always be an on-disk blob record size.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10248

Reviewed By: ltamasi

Differential Revision: D37470292

Pulled By: gangliao

fbshipit-source-id: fbca521b2791d3674dbf2484cea5fcae2fdd94d2
2022-06-27 17:15:21 -07:00
Gang Liao ba1f62ddfb Read from blob cache first when MultiGetBlob() (#10225)
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10225

Test Plan:
Add test cases for MultiGetBlob
In this task, we added the new API MultiGetBlob() for BlobSource.

This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Reviewed By: ltamasi

Differential Revision: D37358364

Pulled By: gangliao

fbshipit-source-id: aff053a37615d96d768fb9aedde17da5618c7ae6
2022-06-23 13:52:00 -07:00
Gang Liao c965c9ef65 Read blob from blob cache if exists when GetBlob() (#10178)
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
In this task, we added a new abstraction layer `BlobSource` to retrieve blobs from either blob cache or raw blob file. Note: For simplicity, the current PR only includes `GetBlob()`.  `MultiGetBlob()` will be included in the next PR.

This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10178

Reviewed By: ltamasi

Differential Revision: D37250507

Pulled By: gangliao

fbshipit-source-id: 3fc4a55a0cea955a3147bdc7dba06430e377259b
2022-06-17 15:22:59 -07:00