1 //  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
2 //  This source code is licensed under both the GPLv2 (found in the
3 //  COPYING file in the root directory) and Apache 2.0 License
4 //  (found in the LICENSE.Apache file in the root directory).
5 //
6 
7 #ifndef ROCKSDB_LITE
8 
9 #include <stdint.h>
10 #include <algorithm>
11 #include <cinttypes>
12 #include <string>
13 #include "db/db_impl/db_impl.h"
14 #include "db/job_context.h"
15 #include "db/version_set.h"
16 #include "file/file_util.h"
17 #include "file/filename.h"
18 #include "port/port.h"
19 #include "rocksdb/db.h"
20 #include "rocksdb/env.h"
21 #include "test_util/sync_point.h"
22 #include "util/mutexlock.h"
23 
24 namespace ROCKSDB_NAMESPACE {
25 
DisableFileDeletions()26 Status DBImpl::DisableFileDeletions() {
27   InstrumentedMutexLock l(&mutex_);
28   ++disable_delete_obsolete_files_;
29   if (disable_delete_obsolete_files_ == 1) {
30     ROCKS_LOG_INFO(immutable_db_options_.info_log, "File Deletions Disabled");
31   } else {
32     ROCKS_LOG_WARN(immutable_db_options_.info_log,
33                    "File Deletions Disabled, but already disabled. Counter: %d",
34                    disable_delete_obsolete_files_);
35   }
36   return Status::OK();
37 }
38 
EnableFileDeletions(bool force)39 Status DBImpl::EnableFileDeletions(bool force) {
40   // Job id == 0 means that this is not our background process, but rather
41   // user thread
42   JobContext job_context(0);
43   bool file_deletion_enabled = false;
44   {
45     InstrumentedMutexLock l(&mutex_);
46     if (force) {
47       // if force, we need to enable file deletions right away
48       disable_delete_obsolete_files_ = 0;
49     } else if (disable_delete_obsolete_files_ > 0) {
50       --disable_delete_obsolete_files_;
51     }
52     if (disable_delete_obsolete_files_ == 0)  {
53       file_deletion_enabled = true;
54       FindObsoleteFiles(&job_context, true);
55       bg_cv_.SignalAll();
56     }
57   }
58   if (file_deletion_enabled) {
59     ROCKS_LOG_INFO(immutable_db_options_.info_log, "File Deletions Enabled");
60     if (job_context.HaveSomethingToDelete()) {
61       PurgeObsoleteFiles(job_context);
62     }
63   } else {
64     ROCKS_LOG_WARN(immutable_db_options_.info_log,
65                    "File Deletions Enable, but not really enabled. Counter: %d",
66                    disable_delete_obsolete_files_);
67   }
68   job_context.Clean();
69   LogFlush(immutable_db_options_.info_log);
70   return Status::OK();
71 }
72 
IsFileDeletionsEnabled() const73 int DBImpl::IsFileDeletionsEnabled() const {
74   return !disable_delete_obsolete_files_;
75 }
76 
GetLiveFiles(std::vector<std::string> & ret,uint64_t * manifest_file_size,bool flush_memtable)77 Status DBImpl::GetLiveFiles(std::vector<std::string>& ret,
78                             uint64_t* manifest_file_size,
79                             bool flush_memtable) {
80   *manifest_file_size = 0;
81 
82   mutex_.Lock();
83 
84   if (flush_memtable) {
85     // flush all dirty data to disk.
86     Status status;
87     if (immutable_db_options_.atomic_flush) {
88       autovector<ColumnFamilyData*> cfds;
89       SelectColumnFamiliesForAtomicFlush(&cfds);
90       mutex_.Unlock();
91       status = AtomicFlushMemTables(cfds, FlushOptions(),
92                                     FlushReason::kGetLiveFiles);
93       mutex_.Lock();
94     } else {
95       for (auto cfd : *versions_->GetColumnFamilySet()) {
96         if (cfd->IsDropped()) {
97           continue;
98         }
99         cfd->Ref();
100         mutex_.Unlock();
101         status = FlushMemTable(cfd, FlushOptions(), FlushReason::kGetLiveFiles);
102         TEST_SYNC_POINT("DBImpl::GetLiveFiles:1");
103         TEST_SYNC_POINT("DBImpl::GetLiveFiles:2");
104         mutex_.Lock();
105         cfd->UnrefAndTryDelete();
106         if (!status.ok()) {
107           break;
108         }
109       }
110     }
111     versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
112 
113     if (!status.ok()) {
114       mutex_.Unlock();
115       ROCKS_LOG_ERROR(immutable_db_options_.info_log, "Cannot Flush data %s\n",
116                       status.ToString().c_str());
117       return status;
118     }
119   }
120 
121   // Make a set of all of the live *.sst files
122   std::vector<FileDescriptor> live;
123   for (auto cfd : *versions_->GetColumnFamilySet()) {
124     if (cfd->IsDropped()) {
125       continue;
126     }
127     cfd->current()->AddLiveFiles(&live);
128   }
129 
130   ret.clear();
131   ret.reserve(live.size() + 3);  // *.sst + CURRENT + MANIFEST + OPTIONS
132 
133   // create names of the live files. The names are not absolute
134   // paths, instead they are relative to dbname_;
135   for (const auto& live_file : live) {
136     ret.push_back(MakeTableFileName("", live_file.GetNumber()));
137   }
138 
139   ret.push_back(CurrentFileName(""));
140   ret.push_back(DescriptorFileName("", versions_->manifest_file_number()));
141   ret.push_back(OptionsFileName("", versions_->options_file_number()));
142 
143   // find length of manifest file while holding the mutex lock
144   *manifest_file_size = versions_->manifest_file_size();
145 
146   mutex_.Unlock();
147   return Status::OK();
148 }
149 
GetSortedWalFiles(VectorLogPtr & files)150 Status DBImpl::GetSortedWalFiles(VectorLogPtr& files) {
151   {
152     // If caller disabled deletions, this function should return files that are
153     // guaranteed not to be deleted until deletions are re-enabled. We need to
154     // wait for pending purges to finish since WalManager doesn't know which
155     // files are going to be purged. Additional purges won't be scheduled as
156     // long as deletions are disabled (so the below loop must terminate).
157     InstrumentedMutexLock l(&mutex_);
158     while (disable_delete_obsolete_files_ > 0 &&
159            pending_purge_obsolete_files_ > 0) {
160       bg_cv_.Wait();
161     }
162   }
163   return wal_manager_.GetSortedWalFiles(files);
164 }
165 
GetCurrentWalFile(std::unique_ptr<LogFile> * current_log_file)166 Status DBImpl::GetCurrentWalFile(std::unique_ptr<LogFile>* current_log_file) {
167   uint64_t current_logfile_number;
168   {
169     InstrumentedMutexLock l(&mutex_);
170     current_logfile_number = logfile_number_;
171   }
172 
173   return wal_manager_.GetLiveWalFile(current_logfile_number, current_log_file);
174 }
175 }  // namespace ROCKSDB_NAMESPACE
176 
177 #endif  // ROCKSDB_LITE
178