rocksdb/db/blob/blob_fetcher.cc
Levi Tamasi dc5de45af8 Support readahead during compaction for blob files (#9187)
Summary:
The patch adds a new BlobDB configuration option `blob_compaction_readahead_size`
that can be used to enable prefetching data from blob files during compaction.
This is important when using storage with higher latencies like HDDs or remote filesystems.
If enabled, prefetching is used for all cases when blobs are read during compaction,
namely garbage collection, compaction filters (when the existing value has to be read from
a blob file), and `Merge` (when the value of the base `Put` is stored in a blob file).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9187

Test Plan: Ran `make check` and the stress/crash test.

Reviewed By: riversand963

Differential Revision: D32565512

Pulled By: ltamasi

fbshipit-source-id: 87be9cebc3aa01cc227bec6b5f64d827b8164f5d
2021-11-19 17:53:47 -08:00

35 lines
1.3 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include "db/blob/blob_fetcher.h"
#include "db/version_set.h"
namespace ROCKSDB_NAMESPACE {
Status BlobFetcher::FetchBlob(const Slice& user_key,
const Slice& blob_index_slice,
FilePrefetchBuffer* prefetch_buffer,
PinnableSlice* blob_value,
uint64_t* bytes_read) const {
assert(version_);
return version_->GetBlob(read_options_, user_key, blob_index_slice,
prefetch_buffer, blob_value, bytes_read);
}
Status BlobFetcher::FetchBlob(const Slice& user_key,
const BlobIndex& blob_index,
FilePrefetchBuffer* prefetch_buffer,
PinnableSlice* blob_value,
uint64_t* bytes_read) const {
assert(version_);
return version_->GetBlob(read_options_, user_key, blob_index, prefetch_buffer,
blob_value, bytes_read);
}
} // namespace ROCKSDB_NAMESPACE