#0 0x00007f1e7929a64d in poll () from /lib64/libc.so.6 #1 0x00007f1e7a06c69c in ?? () from /usr/lib64/libruby.so.2.3 #2 0x00007f1e79cb4dc5 in start_thread () from /lib64/libpthread.so.0 #3 0x00007f1e792a4c9d in clone () from /lib64/libc.so.6 Thread 1 (Thread 0x7f1e7a56b740 (LWP 75934)): #0 0x00007f1e79cb86d5 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0 #1 0x00007f1e6db494ed in leveldb::port::CondVar::Wait() () from /data/app/smart-ad-rtm/vendor/bundle/ruby/2.3/gems/leveldb-0.1.9/ext/leveldb/libleveldb.so #2 0x00007f1e6db1f4aa in leveldb::DBImpl::MakeRoomForWrite(bool) () from /data/app/smart-ad-rtm/vendor/bundle/ruby/2.3/gems/leveldb-0.1.9/ext/leveldb/libleveldb.so #3 0x00007f1e6db22d38 in leveldb::DBImpl::Write(leveldb::WriteOptions const&, leveldb::WriteBatch*) () from /data/app/smart-ad-rtm/vendor/bundle/ruby/2.3/gems/leveldb-0.1.9/ext/leveldb/libleveldb.so #4 0x00007f1e6db1f829 in leveldb::DB::Put(leveldb::WriteOptions const&, leveldb::Slice const&, leveldb::Slice const&) () from /data/app/smart-ad-rtm/vendor/bundle/ruby/2.3/gems/leveldb-0.1.9/ext/leveldb/libleveldb.so #5 0x00007f1e6db1f869 in leveldb::DBImpl::Put(leveldb::WriteOptions const&, leveldb::Slice const&, leveldb::Slice const&) () from /data/app/smart-ad-rtm/vendor/bundle/ruby/2.3/gems/leveldb-0.1.9/ext/leveldb/libleveldb.so #6 0x00007f1e6db1c7a8 in leveldb_put () from /data/app/smart-ad-rtm/vendor/bundle/ruby/2.3/gems/leveldb-0.1.9/ext/leveldb/libleveldb.so #7 0x00007f1e6dd5fcec in ffi_call_unix64 () from /usr/lib64/libffi.so.6