ClickHouse/src/Disks/IStoragePolicy.h
2022-10-25 22:14:06 +00:00

75 lines
3.1 KiB
C++

#pragma once
#include <Disks/DiskType.h>
#include <memory>
#include <vector>
#include <optional>
#include <base/types.h>
namespace DB
{
class IStoragePolicy;
using StoragePolicyPtr = std::shared_ptr<const IStoragePolicy>;
class IVolume;
using VolumePtr = std::shared_ptr<IVolume>;
using Volumes = std::vector<VolumePtr>;
class IDisk;
using DiskPtr = std::shared_ptr<IDisk>;
using Disks = std::vector<DiskPtr>;
class IReservation;
using ReservationSharedPtr = std::shared_ptr<IReservation>;
using ReservationPtr = std::unique_ptr<IReservation>;
using Reservations = std::vector<ReservationPtr>;
using String = std::string;
class IStoragePolicy
{
public:
virtual ~IStoragePolicy() = default;
virtual const String & getName() const = 0;
virtual const Volumes & getVolumes() const = 0;
/// Returns number [0., 1.] -- fraction of free space on disk
/// which should be kept with help of background moves
virtual double getMoveFactor() const = 0;
virtual bool isDefaultPolicy() const = 0;
/// Returns disks ordered by volumes priority
virtual Disks getDisks() const = 0;
/// Returns any disk
/// Used when it's not important, for example for
/// mutations files
virtual DiskPtr getAnyDisk() const = 0;
virtual DiskPtr tryGetDiskByName(const String & disk_name) const = 0;
DiskPtr getDiskByName(const String & disk_name) const;
/// Get free space from most free disk
virtual UInt64 getMaxUnreservedFreeSpace() const = 0;
/// Reserves space on any volume with index > min_volume_index or returns nullptr
virtual ReservationPtr reserve(UInt64 bytes, size_t min_volume_index) const = 0;
/// Returns valid reservation or nullptr
virtual ReservationPtr reserve(UInt64 bytes) const = 0;
/// Reserves space on any volume or throws
virtual ReservationPtr reserveAndCheck(UInt64 bytes) const = 0;
/// Reserves 0 bytes on disk with max available space
/// Do not use this function when it is possible to predict size.
virtual ReservationPtr makeEmptyReservationOnLargestDisk() const = 0;
/// Get volume by index.
virtual VolumePtr getVolume(size_t index) const = 0;
virtual VolumePtr tryGetVolumeByName(const String & volume_name) const = 0;
VolumePtr getVolumeByName(const String & volume_name) const;
/// Checks if storage policy can be replaced by another one.
virtual void checkCompatibleWith(const StoragePolicyPtr & new_storage_policy) const = 0;
/// Finds a volume index, which contains disk
virtual std::optional<size_t> tryGetVolumeIndexByDiskName(const String & disk_name) const = 0;
size_t getVolumeIndexByDiskName(const String & disk_name) const;
/// Finds a volume which contains a specified disk.
VolumePtr tryGetVolumeByDiskName(const String & disk_name) const;
VolumePtr getVolumeByDiskName(const String & disk_name) const;
/// Check if we have any volume with stopped merges
virtual bool hasAnyVolumeWithDisabledMerges() const = 0;
virtual bool containsVolume(const String & volume_name) const = 0;
/// Returns disks by type ordered by volumes priority
};
}