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90 lines
2.6 KiB
Go
90 lines
2.6 KiB
Go
// Copyright 2015 The etcd Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package raft
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import pb "github.com/pingcap-incubator/tinykv/proto/pkg/eraftpb"
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// RaftLog manage the log entries, its struct look like:
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//
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// snapshot/first.....applied....committed....stabled.....last
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// --------|------------------------------------------------|
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// log entries
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//
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// for simplify the RaftLog implement should manage all log entries
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// that not truncated
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type RaftLog struct {
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// storage contains all stable entries since the last snapshot.
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storage Storage
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// committed is the highest log position that is known to be in
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// stable storage on a quorum of nodes.
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committed uint64
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// applied is the highest log position that the application has
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// been instructed to apply to its state machine.
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// Invariant: applied <= committed
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applied uint64
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// log entries with index <= stabled are stabled to storage
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stabled uint64
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// all entries that have not yet compact.
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entries []pb.Entry
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// the incoming unstable snapshot, if any.
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// (Used in 2C)
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pendingSnapshot *pb.Snapshot
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// Your Data Here (2A).
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}
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// newLog returns log using the given storage. It recovers the log
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// to the state that it just commits and applies the latest snapshot.
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func newLog(storage Storage) *RaftLog {
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// Your Code Here (2A).
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return nil
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}
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// We need to compact the log entries in some point of time like
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// storage compact stabled log entries prevent the log entries
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// grow unlimitedly in memory
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func (l *RaftLog) maybeCompact() {
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// Your Code Here (2C).
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}
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// unstableEntries return all the unstable entries
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func (l *RaftLog) unstableEntries() []pb.Entry {
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// Your Code Here (2A).
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return nil
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}
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// nextEnts returns all the committed but not applied entries
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func (l *RaftLog) nextEnts() (ents []pb.Entry) {
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// Your Code Here (2A).
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return nil
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}
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// LastIndex return the last index of the lon entries
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func (l *RaftLog) LastIndex() uint64 {
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// Your Code Here (2A).
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return 0
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}
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// Term return the term of the entry in the given index
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func (l *RaftLog) Term(i uint64) (uint64, error) {
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// Your Code Here (2A).
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return 0, nil
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}
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