milvus/internal/core/src/storage/ChunkCache.cpp

136 lines
4.1 KiB
C++

// Licensed to the LF AI & Data foundation under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "ChunkCache.h"
#include "mmap/Utils.h"
namespace milvus::storage {
std::shared_ptr<ColumnBase>
ChunkCache::Read(const std::string& filepath) {
auto path = CachePath(filepath);
{
std::shared_lock lck(mutex_);
auto it = columns_.find(path);
if (it != columns_.end()) {
AssertInfo(it->second, "unexpected null column, file={}", filepath);
return it->second;
}
}
auto field_data = DownloadAndDecodeRemoteFile(cm_.get(), filepath);
std::unique_lock lck(mutex_);
auto it = columns_.find(path);
if (it != columns_.end()) {
return it->second;
}
auto column = Mmap(path, field_data->GetFieldData());
AssertInfo(column, "unexpected null column, file={}", filepath);
columns_.emplace(path, column);
return column;
}
void
ChunkCache::Remove(const std::string& filepath) {
auto path = CachePath(filepath);
std::unique_lock lck(mutex_);
columns_.erase(path);
}
void
ChunkCache::Prefetch(const std::string& filepath) {
auto path = CachePath(filepath);
std::shared_lock lck(mutex_);
auto it = columns_.find(path);
if (it == columns_.end()) {
return;
}
auto column = it->second;
auto ok =
madvise(reinterpret_cast<void*>(const_cast<char*>(column->Data())),
column->ByteSize(),
read_ahead_policy_);
AssertInfo(ok == 0,
"failed to madvise to the data file {}, err: {}",
path,
strerror(errno));
}
std::shared_ptr<ColumnBase>
ChunkCache::Mmap(const std::filesystem::path& path,
const FieldDataPtr& field_data) {
auto dir = path.parent_path();
std::filesystem::create_directories(dir);
auto dim = field_data->get_dim();
auto data_type = field_data->get_data_type();
auto file = File::Open(path.string(), O_CREAT | O_TRUNC | O_RDWR);
// write the field data to disk
auto data_size = field_data->Size();
// unused
std::vector<std::vector<uint64_t>> element_indices{};
auto written = WriteFieldData(file, data_type, field_data, element_indices);
AssertInfo(written == data_size,
"failed to write data file {}, written "
"{} but total {}, err: {}",
path.c_str(),
written,
data_size,
strerror(errno));
std::shared_ptr<ColumnBase> column{};
if (datatype_is_variable(data_type)) {
AssertInfo(
false, "TODO: unimplemented for variable data type: {}", data_type);
} else {
column = std::make_shared<Column>(file, data_size, dim, data_type);
}
// unlink
auto ok = unlink(path.c_str());
AssertInfo(ok == 0,
"failed to unlink mmap data file {}, err: {}",
path.c_str(),
strerror(errno));
return column;
}
std::string
ChunkCache::CachePath(const std::string& filepath) {
auto path = std::filesystem::path(filepath);
auto prefix = std::filesystem::path(path_prefix_);
// Cache path shall not use absolute filepath direct, it shall always under path_prefix_
if (path.is_absolute()) {
return (prefix /
filepath.substr(path.root_directory().string().length(),
filepath.length()))
.string();
}
return (prefix / filepath).string();
}
} // namespace milvus::storage