Bug Summary

File:home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc
Warning:line 243, column 9
Value stored to 'total_penlty' is never read

Annotated Source Code

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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#ifndef ROCKSDB_LITE
7
8#include "util/delete_scheduler.h"
9
10#include <thread>
11#include <vector>
12
13#include "port/port.h"
14#include "rocksdb/env.h"
15#include "util/logging.h"
16#include "util/mutexlock.h"
17#include "util/sst_file_manager_impl.h"
18#include "util/sync_point.h"
19
20namespace rocksdb {
21
22DeleteScheduler::DeleteScheduler(Env* env, int64_t rate_bytes_per_sec,
23 Logger* info_log,
24 SstFileManagerImpl* sst_file_manager,
25 double max_trash_db_ratio,
26 uint64_t bytes_max_delete_chunk)
27 : env_(env),
28 total_trash_size_(0),
29 rate_bytes_per_sec_(rate_bytes_per_sec),
30 pending_files_(0),
31 bytes_max_delete_chunk_(bytes_max_delete_chunk),
32 closing_(false),
33 cv_(&mu_),
34 info_log_(info_log),
35 sst_file_manager_(sst_file_manager),
36 max_trash_db_ratio_(max_trash_db_ratio) {
37 assert(sst_file_manager != nullptr)(static_cast<void> (0));
38 assert(max_trash_db_ratio >= 0)(static_cast<void> (0));
39 bg_thread_.reset(
40 new port::Thread(&DeleteScheduler::BackgroundEmptyTrash, this));
41}
42
43DeleteScheduler::~DeleteScheduler() {
44 {
45 InstrumentedMutexLock l(&mu_);
46 closing_ = true;
47 cv_.SignalAll();
48 }
49 if (bg_thread_) {
50 bg_thread_->join();
51 }
52}
53
54Status DeleteScheduler::DeleteFile(const std::string& file_path,
55 const std::string& dir_to_sync,
56 const bool force_bg) {
57 Status s;
58 if (rate_bytes_per_sec_.load() <= 0 || (!force_bg &&
59 total_trash_size_.load() >
60 sst_file_manager_->GetTotalSize() * max_trash_db_ratio_.load())) {
61 // Rate limiting is disabled or trash size makes up more than
62 // max_trash_db_ratio_ (default 25%) of the total DB size
63 TEST_SYNC_POINT("DeleteScheduler::DeleteFile");
64 s = env_->DeleteFile(file_path);
65 if (s.ok()) {
66 sst_file_manager_->OnDeleteFile(file_path);
67 }
68 return s;
69 }
70
71 // Move file to trash
72 std::string trash_file;
73 s = MarkAsTrash(file_path, &trash_file);
74
75 if (!s.ok()) {
76 ROCKS_LOG_ERROR(info_log_, "Failed to mark %s as trash", file_path.c_str())rocksdb::Log(InfoLogLevel::ERROR_LEVEL, info_log_, ("[%s:" "76"
"] " "Failed to mark %s as trash"), RocksLogShorterFileName(
"/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), file_path.c_str());
77 s = env_->DeleteFile(file_path);
78 if (s.ok()) {
79 sst_file_manager_->OnDeleteFile(file_path);
80 }
81 return s;
82 }
83
84 // Update the total trash size
85 uint64_t trash_file_size = 0;
86 env_->GetFileSize(trash_file, &trash_file_size);
87 total_trash_size_.fetch_add(trash_file_size);
88
89 // Add file to delete queue
90 {
91 InstrumentedMutexLock l(&mu_);
92 queue_.emplace(trash_file, dir_to_sync);
93 pending_files_++;
94 if (pending_files_ == 1) {
95 cv_.SignalAll();
96 }
97 }
98 return s;
99}
100
101std::map<std::string, Status> DeleteScheduler::GetBackgroundErrors() {
102 InstrumentedMutexLock l(&mu_);
103 return bg_errors_;
104}
105
106const std::string DeleteScheduler::kTrashExtension = ".trash";
107bool DeleteScheduler::IsTrashFile(const std::string& file_path) {
108 return (file_path.size() >= kTrashExtension.size() &&
109 file_path.rfind(kTrashExtension) ==
110 file_path.size() - kTrashExtension.size());
111}
112
113Status DeleteScheduler::CleanupDirectory(Env* env, SstFileManagerImpl* sfm,
114 const std::string& path) {
115 Status s;
116 // Check if there are any files marked as trash in this path
117 std::vector<std::string> files_in_path;
118 s = env->GetChildren(path, &files_in_path);
119 if (!s.ok()) {
120 return s;
121 }
122 for (const std::string& current_file : files_in_path) {
123 if (!DeleteScheduler::IsTrashFile(current_file)) {
124 // not a trash file, skip
125 continue;
126 }
127
128 Status file_delete;
129 std::string trash_file = path + "/" + current_file;
130 if (sfm) {
131 // We have an SstFileManager that will schedule the file delete
132 sfm->OnAddFile(trash_file);
133 file_delete = sfm->ScheduleFileDeletion(trash_file, path);
134 } else {
135 // Delete the file immediately
136 file_delete = env->DeleteFile(trash_file);
137 }
138
139 if (s.ok() && !file_delete.ok()) {
140 s = file_delete;
141 }
142 }
143
144 return s;
145}
146
147Status DeleteScheduler::MarkAsTrash(const std::string& file_path,
148 std::string* trash_file) {
149 // Sanity check of the path
150 size_t idx = file_path.rfind("/");
151 if (idx == std::string::npos || idx == file_path.size() - 1) {
152 return Status::InvalidArgument("file_path is corrupted");
153 }
154
155 Status s;
156 if (DeleteScheduler::IsTrashFile(file_path)) {
157 // This is already a trash file
158 *trash_file = file_path;
159 return s;
160 }
161
162 *trash_file = file_path + kTrashExtension;
163 // TODO(tec) : Implement Env::RenameFileIfNotExist and remove
164 // file_move_mu mutex.
165 int cnt = 0;
166 InstrumentedMutexLock l(&file_move_mu_);
167 while (true) {
168 s = env_->FileExists(*trash_file);
169 if (s.IsNotFound()) {
170 // We found a path for our file in trash
171 s = env_->RenameFile(file_path, *trash_file);
172 break;
173 } else if (s.ok()) {
174 // Name conflict, generate new random suffix
175 *trash_file = file_path + std::to_string(cnt) + kTrashExtension;
176 } else {
177 // Error during FileExists call, we cannot continue
178 break;
179 }
180 cnt++;
181 }
182 if (s.ok()) {
183 sst_file_manager_->OnMoveFile(file_path, *trash_file);
184 }
185 return s;
186}
187
188void DeleteScheduler::BackgroundEmptyTrash() {
189 TEST_SYNC_POINT("DeleteScheduler::BackgroundEmptyTrash");
190
191 while (true) {
192 InstrumentedMutexLock l(&mu_);
193 while (queue_.empty() && !closing_) {
194 cv_.Wait();
195 }
196
197 if (closing_) {
198 return;
199 }
200
201 // Delete all files in queue_
202 uint64_t start_time = env_->NowMicros();
203 uint64_t total_deleted_bytes = 0;
204 int64_t current_delete_rate = rate_bytes_per_sec_.load();
205 while (!queue_.empty() && !closing_) {
206 if (current_delete_rate != rate_bytes_per_sec_.load()) {
207 // User changed the delete rate
208 current_delete_rate = rate_bytes_per_sec_.load();
209 start_time = env_->NowMicros();
210 total_deleted_bytes = 0;
211 }
212
213 // Get new file to delete
214 const FileAndDir& fad = queue_.front();
215 std::string path_in_trash = fad.fname;
216
217 // We dont need to hold the lock while deleting the file
218 mu_.Unlock();
219 uint64_t deleted_bytes = 0;
220 bool is_complete = true;
221 // Delete file from trash and update total_penlty value
222 Status s =
223 DeleteTrashFile(path_in_trash, fad.dir, &deleted_bytes, &is_complete);
224 total_deleted_bytes += deleted_bytes;
225 mu_.Lock();
226 if (is_complete) {
227 queue_.pop();
228 }
229
230 if (!s.ok()) {
231 bg_errors_[path_in_trash] = s;
232 }
233
234 // Apply penlty if necessary
235 uint64_t total_penlty;
236 if (current_delete_rate > 0) {
237 // rate limiting is enabled
238 total_penlty =
239 ((total_deleted_bytes * kMicrosInSecond) / current_delete_rate);
240 while (!closing_ && !cv_.TimedWait(start_time + total_penlty)) {}
241 } else {
242 // rate limiting is disabled
243 total_penlty = 0;
Value stored to 'total_penlty' is never read
244 }
245 TEST_SYNC_POINT_CALLBACK("DeleteScheduler::BackgroundEmptyTrash:Wait",
246 &total_penlty);
247
248 if (is_complete) {
249 pending_files_--;
250 }
251 if (pending_files_ == 0) {
252 // Unblock WaitForEmptyTrash since there are no more files waiting
253 // to be deleted
254 cv_.SignalAll();
255 }
256 }
257 }
258}
259
260Status DeleteScheduler::DeleteTrashFile(const std::string& path_in_trash,
261 const std::string& dir_to_sync,
262 uint64_t* deleted_bytes,
263 bool* is_complete) {
264 uint64_t file_size;
265 Status s = env_->GetFileSize(path_in_trash, &file_size);
266 *is_complete = true;
267 TEST_SYNC_POINT("DeleteScheduler::DeleteTrashFile:DeleteFile");
268 if (s.ok()) {
269 bool need_full_delete = true;
270 if (bytes_max_delete_chunk_ != 0 && file_size > bytes_max_delete_chunk_) {
271 uint64_t num_hard_links = 2;
272 // We don't have to worry aobut data race between linking a new
273 // file after the number of file link check and ftruncte because
274 // the file is now in trash and no hardlink is supposed to create
275 // to trash files by RocksDB.
276 Status my_status = env_->NumFileLinks(path_in_trash, &num_hard_links);
277 if (my_status.ok()) {
278 if (num_hard_links == 1) {
279 std::unique_ptr<WritableFile> wf;
280 my_status =
281 env_->ReopenWritableFile(path_in_trash, &wf, EnvOptions());
282 if (my_status.ok()) {
283 my_status = wf->Truncate(file_size - bytes_max_delete_chunk_);
284 if (my_status.ok()) {
285 TEST_SYNC_POINT("DeleteScheduler::DeleteTrashFile:Fsync");
286 my_status = wf->Fsync();
287 }
288 }
289 if (my_status.ok()) {
290 *deleted_bytes = bytes_max_delete_chunk_;
291 need_full_delete = false;
292 *is_complete = false;
293 } else {
294 ROCKS_LOG_WARN(info_log_,rocksdb::Log(InfoLogLevel::WARN_LEVEL, info_log_, ("[%s:" "296"
"] " "Failed to partially delete %s from trash -- %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str(), my_status.ToString().c_str())
295 "Failed to partially delete %s from trash -- %s",rocksdb::Log(InfoLogLevel::WARN_LEVEL, info_log_, ("[%s:" "296"
"] " "Failed to partially delete %s from trash -- %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str(), my_status.ToString().c_str())
296 path_in_trash.c_str(), my_status.ToString().c_str())rocksdb::Log(InfoLogLevel::WARN_LEVEL, info_log_, ("[%s:" "296"
"] " "Failed to partially delete %s from trash -- %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str(), my_status.ToString().c_str());
297 }
298 } else {
299 ROCKS_LOG_INFO(info_log_,rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "302"
"] " "Cannot delete %s slowly through ftruncate from trash "
"as it has other links"), RocksLogShorterFileName("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str())
300 "Cannot delete %s slowly through ftruncate from trash "rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "302"
"] " "Cannot delete %s slowly through ftruncate from trash "
"as it has other links"), RocksLogShorterFileName("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str())
301 "as it has other links",rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "302"
"] " "Cannot delete %s slowly through ftruncate from trash "
"as it has other links"), RocksLogShorterFileName("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str())
302 path_in_trash.c_str())rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "302"
"] " "Cannot delete %s slowly through ftruncate from trash "
"as it has other links"), RocksLogShorterFileName("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str());
303 }
304 } else if (!num_link_error_printed_) {
305 ROCKS_LOG_INFO(rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "309"
"] " "Cannot delete files slowly through ftruncate from trash "
"as Env::NumFileLinks() returns error: %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), my_status.ToString().c_str())
306 info_log_,rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "309"
"] " "Cannot delete files slowly through ftruncate from trash "
"as Env::NumFileLinks() returns error: %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), my_status.ToString().c_str())
307 "Cannot delete files slowly through ftruncate from trash "rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "309"
"] " "Cannot delete files slowly through ftruncate from trash "
"as Env::NumFileLinks() returns error: %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), my_status.ToString().c_str())
308 "as Env::NumFileLinks() returns error: %s",rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "309"
"] " "Cannot delete files slowly through ftruncate from trash "
"as Env::NumFileLinks() returns error: %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), my_status.ToString().c_str())
309 my_status.ToString().c_str())rocksdb::Log(InfoLogLevel::INFO_LEVEL, info_log_, ("[%s:" "309"
"] " "Cannot delete files slowly through ftruncate from trash "
"as Env::NumFileLinks() returns error: %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), my_status.ToString().c_str());
310 num_link_error_printed_ = true;
311 }
312 }
313
314 if (need_full_delete) {
315 s = env_->DeleteFile(path_in_trash);
316 if (!dir_to_sync.empty()) {
317 std::unique_ptr<Directory> dir_obj;
318 if (s.ok()) {
319 s = env_->NewDirectory(dir_to_sync, &dir_obj);
320 }
321 if (s.ok()) {
322 s = dir_obj->Fsync();
323 TEST_SYNC_POINT_CALLBACK(
324 "DeleteScheduler::DeleteTrashFile::AfterSyncDir",
325 reinterpret_cast<void*>(const_cast<std::string*>(&dir_to_sync)));
326 }
327 }
328 *deleted_bytes = file_size;
329 sst_file_manager_->OnDeleteFile(path_in_trash);
330 }
331 }
332 if (!s.ok()) {
333 // Error while getting file size or while deleting
334 ROCKS_LOG_ERROR(info_log_, "Failed to delete %s from trash -- %s",rocksdb::Log(InfoLogLevel::ERROR_LEVEL, info_log_, ("[%s:" "335"
"] " "Failed to delete %s from trash -- %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str(), s.ToString().c_str())
335 path_in_trash.c_str(), s.ToString().c_str())rocksdb::Log(InfoLogLevel::ERROR_LEVEL, info_log_, ("[%s:" "335"
"] " "Failed to delete %s from trash -- %s"), RocksLogShorterFileName
("/home/bhubbard/working/src/ceph/src/rocksdb/util/delete_scheduler.cc"
), path_in_trash.c_str(), s.ToString().c_str());
336 *deleted_bytes = 0;
337 } else {
338 total_trash_size_.fetch_sub(*deleted_bytes);
339 }
340
341 return s;
342}
343
344void DeleteScheduler::WaitForEmptyTrash() {
345 InstrumentedMutexLock l(&mu_);
346 while (pending_files_ > 0 && !closing_) {
347 cv_.Wait();
348 }
349}
350
351} // namespace rocksdb
352
353#endif // ROCKSDB_LITE