rocksdb/db/blob_file_state.cc
Levi Tamasi d87c10c6ab Add blob file state to VersionEdit (#6416)
Summary:
BlobDB currently does not keep track of blob files: no records are written to
the manifest when a blob file is added or removed, and upon opening a database,
the list of blob files is populated simply based on the contents of the blob directory.
This means that lost blob files cannot be detected at the moment. We plan to solve
this issue by making blob files a part of `Version`; as a first step, this patch makes
it possible to store information about blob files in `VersionEdit`. Currently, this information
includes blob file number, total number and size of all blobs, and total number and size
of garbage blobs. However, the format is extensible: new fields can be added in
both a forward compatible and a forward incompatible manner if needed (similarly
to `kNewFile4`).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6416

Test Plan: `make check`

Differential Revision: D19894234

Pulled By: ltamasi

fbshipit-source-id: f9753e1f2aedf6dadb70c09b345207cb9c58c329
2020-02-24 18:39:53 -08:00

174 lines
5.4 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_file_state.h"
#include "logging/event_logger.h"
#include "rocksdb/slice.h"
#include "rocksdb/status.h"
#include "test_util/sync_point.h"
#include "util/coding.h"
#include <ostream>
#include <sstream>
namespace ROCKSDB_NAMESPACE {
namespace {
// Tags for custom fields. Note that these get persisted in the manifest,
// so existing tags should not be modified.
enum CustomFieldTags : uint32_t {
kEndMarker,
// Add forward compatible fields here
/////////////////////////////////////////////////////////////////////
kForwardIncompatibleMask = 1 << 6,
// Add forward incompatible fields here
};
} // anonymous namespace
void BlobFileState::EncodeTo(std::string* output) const {
PutVarint64(output, blob_file_number_);
PutVarint64(output, total_blob_count_);
PutVarint64(output, total_blob_bytes_);
PutVarint64(output, garbage_blob_count_);
PutVarint64(output, garbage_blob_bytes_);
PutLengthPrefixedSlice(output, checksum_method_);
PutLengthPrefixedSlice(output, checksum_value_);
// Encode any custom fields here. The format to use is a Varint32 tag (see
// CustomFieldTags above) followed by a length prefixed slice. Unknown custom
// fields will be ignored during decoding unless they're in the forward
// incompatible range.
TEST_SYNC_POINT_CALLBACK("BlobFileState::EncodeTo::CustomFields", output);
PutVarint32(output, kEndMarker);
}
Status BlobFileState::DecodeFrom(Slice* input) {
constexpr char class_name[] = "BlobFileState";
if (!GetVarint64(input, &blob_file_number_)) {
return Status::Corruption(class_name, "Error decoding blob file number");
}
if (!GetVarint64(input, &total_blob_count_)) {
return Status::Corruption(class_name, "Error decoding total blob count");
}
if (!GetVarint64(input, &total_blob_bytes_)) {
return Status::Corruption(class_name, "Error decoding total blob bytes");
}
if (!GetVarint64(input, &garbage_blob_count_)) {
return Status::Corruption(class_name, "Error decoding garbage blob count");
}
if (!GetVarint64(input, &garbage_blob_bytes_)) {
return Status::Corruption(class_name, "Error decoding garbage blob bytes");
}
Slice checksum_method;
if (!GetLengthPrefixedSlice(input, &checksum_method)) {
return Status::Corruption(class_name, "Error decoding checksum method");
}
checksum_method_ = checksum_method.ToString();
Slice checksum_value;
if (!GetLengthPrefixedSlice(input, &checksum_value)) {
return Status::Corruption(class_name, "Error decoding checksum value");
}
checksum_value_ = checksum_value.ToString();
while (true) {
uint32_t custom_field_tag = 0;
if (!GetVarint32(input, &custom_field_tag)) {
return Status::Corruption(class_name, "Error decoding custom field tag");
}
if (custom_field_tag == kEndMarker) {
break;
}
if (custom_field_tag & kForwardIncompatibleMask) {
return Status::Corruption(
class_name, "Forward incompatible custom field encountered");
}
Slice custom_field_value;
if (!GetLengthPrefixedSlice(input, &custom_field_value)) {
return Status::Corruption(class_name,
"Error decoding custom field value");
}
}
return Status::OK();
}
std::string BlobFileState::DebugString() const {
std::ostringstream oss;
oss << *this;
return oss.str();
}
std::string BlobFileState::DebugJSON() const {
JSONWriter jw;
jw << *this;
jw.EndObject();
return jw.Get();
}
bool operator==(const BlobFileState& lhs, const BlobFileState& rhs) {
return lhs.GetBlobFileNumber() == rhs.GetBlobFileNumber() &&
lhs.GetTotalBlobCount() == rhs.GetTotalBlobCount() &&
lhs.GetTotalBlobBytes() == rhs.GetTotalBlobBytes() &&
lhs.GetGarbageBlobCount() == rhs.GetGarbageBlobCount() &&
lhs.GetGarbageBlobBytes() == rhs.GetGarbageBlobBytes() &&
lhs.GetChecksumMethod() == rhs.GetChecksumMethod() &&
lhs.GetChecksumValue() == rhs.GetChecksumValue();
}
bool operator!=(const BlobFileState& lhs, const BlobFileState& rhs) {
return !(lhs == rhs);
}
std::ostream& operator<<(std::ostream& os,
const BlobFileState& blob_file_state) {
os << "blob_file_number: " << blob_file_state.GetBlobFileNumber()
<< " total_blob_count: " << blob_file_state.GetTotalBlobCount()
<< " total_blob_bytes: " << blob_file_state.GetTotalBlobBytes()
<< " garbage_blob_count: " << blob_file_state.GetGarbageBlobCount()
<< " garbage_blob_bytes: " << blob_file_state.GetGarbageBlobBytes()
<< " checksum_method: " << blob_file_state.GetChecksumMethod()
<< " checksum_value: " << blob_file_state.GetChecksumValue();
return os;
}
JSONWriter& operator<<(JSONWriter& jw, const BlobFileState& blob_file_state) {
jw << "BlobFileNumber" << blob_file_state.GetBlobFileNumber()
<< "TotalBlobCount" << blob_file_state.GetTotalBlobCount()
<< "TotalBlobBytes" << blob_file_state.GetTotalBlobBytes()
<< "GarbageBlobCount" << blob_file_state.GetGarbageBlobCount()
<< "GarbageBlobBytes" << blob_file_state.GetGarbageBlobBytes()
<< "ChecksumMethod" << blob_file_state.GetChecksumMethod()
<< "ChecksumValue" << blob_file_state.GetChecksumValue();
return jw;
}
} // namespace ROCKSDB_NAMESPACE