当我在 linux 上运行 pstack {pid} 时,有时会显示??一些记录。这是什么原因?如果只是优化,我怎么知道真正的相关代码?
#0 0x00000037d620b3dc in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
#1 0x00000000008c83db in boost::condition_variable::wait(boost::unique_lock<boost::mutex>&) ()
#2 0x0000000000d95f7b in mongo::SimpleRWLock::lock_shared() ()
#3 0x00000000008bce47 in mongo::Lock::DBRead::lockOther(mongo::StringData const&) ()
#4 0x00000000008bfc86 in mongo::Lock::DBRead::lockDB(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
#5 0x00000000008c1eb0 in mongo::Lock::DBRead::DBRead(mongo::StringData const&) ()
#6 0x000000000081fa35 in mongo::Client::ReadContext::ReadContext(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) ()
**#7 0x0000000000b852bb in ?? ()**
#8 0x00000000008ab646 in mongo::CmdServerStatus::run(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, mongo::BSONObj&, int, std::basic_string<char, std::char_traits<char>, std::allocator<char> >&, mongo::BSONObjBuilder&, bool) ()