foundationdb/fdbserver/MoveKeys.actor.h

112 lines
5.0 KiB
C++

/*
* MoveKeys.actor.h
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2022 Apple Inc. and the FoundationDB project authors
*
* Licensed 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.
*/
#pragma once
#if defined(NO_INTELLISENSE) && !defined(FDBSERVER_MOVEKEYS_ACTOR_G_H)
#define FDBSERVER_MOVEKEYS_ACTOR_G_H
#include "fdbserver/MoveKeys.actor.g.h"
#elif !defined(FDBSERVER_MOVEKEYS_ACTOR_H)
#define FDBSERVER_MOVEKEYS_ACTOR_H
#include "fdbclient/NativeAPI.actor.h"
#include "fdbclient/CommitTransaction.h"
#include "fdbclient/KeyRangeMap.h"
#include "fdbserver/MasterInterface.h"
#include "flow/actorcompiler.h"
struct MoveKeysLock {
UID prevOwner, myOwner, prevWrite;
template <class Ar>
void serialize(Ar& ar) {
serializer(ar, prevOwner, myOwner, prevWrite);
}
};
class DDEnabledState {
// in-memory flag to disable DD
bool ddEnabled = true;
UID ddEnabledStatusUID;
public:
// checks if DD is enabled/disable transiently
bool isDDEnabled() const;
// transiently enable(true) or disable(false) the DD. If the process
// restarts, the state will be forgotten.
bool setDDEnabled(bool status, UID snapUID);
};
// Calling moveKeys, etc with the return value of this actor ensures that no movekeys, etc
// has been executed by a different locker since takeMoveKeysLock(), as calling
// takeMoveKeysLock() updates "moveKeysLockOwnerKey" to a random UID.
ACTOR Future<MoveKeysLock> takeMoveKeysLock(Database cx, UID ddId);
// Checks that the a moveKeysLock has not changed since having taken it
// This does not modify the moveKeysLock
Future<Void> checkMoveKeysLockReadOnly(Transaction* tr, MoveKeysLock lock, const DDEnabledState* ddEnabledState);
void seedShardServers(Arena& trArena, CommitTransactionRef& tr, std::vector<StorageServerInterface> servers);
// Called by the master server to write the very first transaction to the database
// establishing a set of shard servers and all invariants of the systemKeys.
ACTOR Future<Void> moveKeys(Database occ,
KeyRange keys,
std::vector<UID> destinationTeam,
std::vector<UID> healthyDestinations,
MoveKeysLock lock,
Promise<Void> dataMovementComplete,
FlowLock* startMoveKeysParallelismLock,
FlowLock* finishMoveKeysParallelismLock,
bool hasRemote,
UID relocationIntervalId, // for logging only
const DDEnabledState* ddEnabledState);
// Eventually moves the given keys to the given destination team
// Caller is responsible for cancelling it before issuing an overlapping move,
// for restarting the remainder, and for not otherwise cancelling it before
// it returns (since it needs to execute the finishMoveKeys transaction).
ACTOR Future<std::pair<Version, Tag>> addStorageServer(Database cx, StorageServerInterface server);
// Adds a newly recruited storage server to a database (e.g. adding it to FF/serverList)
// Returns a Version in which the storage server is in the database
// This doesn't need to be called for the "seed" storage servers (see seedShardServers above)
ACTOR Future<Void> removeStorageServer(Database cx,
UID serverID,
Optional<UID> tssPairID, // if serverID is a tss, set to its ss pair id
MoveKeysLock lock,
const DDEnabledState* ddEnabledState);
// Removes the given storage server permanently from the database. It must already
// have no shards assigned to it. The storage server MUST NOT be added again after this
// (though a new storage server with a new unique ID may be recruited from the same fdbserver).
ACTOR Future<bool> canRemoveStorageServer(Reference<ReadYourWritesTransaction> tr, UID serverID);
// Returns true if the given storage server has no keys assigned to it and may be safely removed
// Obviously that could change later!
ACTOR Future<Void> removeKeysFromFailedServer(Database cx,
UID serverID,
std::vector<UID> teamForDroppedRange,
MoveKeysLock lock,
const DDEnabledState* ddEnabledState);
// Directly removes serverID from serverKeys and keyServers system keyspace.
// Performed when a storage server is marked as permanently failed.
#include "flow/unactorcompiler.h"
#endif