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Alexey Serbin commented on KUDU-3119: ------------------------------------- One more instance of TSAN race report, log is attached. [^kudu-tool-test.20200709.txt.xz] I guess there is real race if trying to add a block at the same index from two different threads. Yes, there is a lock per index, but consider what happens when two threads trying to access using {{operator[]}} if an element at the index which was not present: {noformat} bool LogBlockManager::AddLogBlock(LogBlockRefPtr lb) { // InsertIfNotPresent doesn't use move semantics, so instead we just // insert an empty scoped_refptr and assign into it down below rather // than using the utility function. int index = lb->block_id().id() & kBlockMapMask; std::lock_guard<simple_spinlock> l(*managed_block_shards_[index].lock); auto& blocks_by_block_id = *managed_block_shards_[index].blocks_by_block_id; LogBlockRefPtr* entry_ptr = &blocks_by_block_id[lb->block_id()]; if (*entry_ptr) { // Already have an entry for this block ID. return false; } ... {noformat} > ToolTest.TestFsAddRemoveDataDirEndToEnd reports race under TSAN > --------------------------------------------------------------- > > Key: KUDU-3119 > URL: https://issues.apache.org/jira/browse/KUDU-3119 > Project: Kudu > Issue Type: Bug > Components: CLI, test > Reporter: Alexey Serbin > Priority: Minor > Attachments: kudu-tool-test.20200709.txt.xz, kudu-tool-test.log.xz > > > Sometimes the {{TestFsAddRemoveDataDirEndToEnd}} scenario of the {{ToolTest}} > reports races for TSAN builds: > {noformat} > /data0/somelongdirectorytoavoidrpathissues/src/kudu/src/kudu/tools/kudu-tool-test.cc:266: > Failure > Failed > Bad status: Runtime error: /tmp/dist-test-taskIZqSmU/build/tsan/bin/kudu: > process exited with non-ze > ro status 66 > Google Test trace: > /data0/somelongdirectorytoavoidrpathissues/src/kudu/src/kudu/tools/kudu-tool-test.cc:265: > W0506 17:5 > 6:02.744191 4432 flags.cc:404] Enabled unsafe flag: --never_fsync=true > I0506 17:56:02.780252 4432 fs_manager.cc:263] Metadata directory not provided > I0506 17:56:02.780442 4432 fs_manager.cc:269] Using write-ahead log > directory (fs_wal_dir) as metad > ata directory > I0506 17:56:02.789638 4432 fs_manager.cc:399] Time spent opening directory > manager: real 0.007s > user 0.005s sys 0.002s > I0506 17:56:02.789986 4432 env_posix.cc:1676] Not raising this process' open > files per process limi > t of 1048576; it is already as high as it can go > I0506 17:56:02.790426 4432 file_cache.cc:465] Constructed file cache lbm > with capacity 419430 > ================== > WARNING: ThreadSanitizer: data race (pid=4432) > ... > {noformat} > The log is attached. -- This message was sent by Atlassian Jira (v8.3.4#803005)