(gdb) bt full
#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
        tid = <optimized out>
        ret = 0
        pd = <optimized out>
        old_mask = {__val = {140318217269728}}
        ret = <optimized out>
#1  0x00007f9f012a9d9f in __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
No locals.
#2  0x00007f9f0125af32 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
        ret = <optimized out>
#3  0x00007f9f01245472 in __GI_abort () at ./stdlib/abort.c:79
        save_stage = 1
        act = {__sigaction_handler = {sa_handler = 0x20, sa_sigaction = 0x20}, sa_mask = {__val = {3028047670040617256, 15778275592715398862, 1167473638900018442, 8802613680540582223, 15490699135259724568, 10737466404784238883, 7355042410906142791, 
              140318217269856, 140320823153936, 0, 140320896061161, 140320897443456, 140320896062195, 140320897443456, 10, 140318217316032}}, sa_flags = 19515514, sa_restorer = 0x7f9e1126e998}
#4  0x00007f9f016cd7fc in __gnu_cxx::__verbose_terminate_handler () at /tmp/deploy/objdir/../gcc-10.2.0/libstdc++-v3/libsupc++/vterminate.cc:95
        terminating = false
        t = <optimized out>
#5  0x0000000000c86f26 in backtrace_terminate_handler () at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/utilities/terminate_handler.cc:88
No locals.
#6  0x00007f9f016d8ab6 in __cxxabiv1::__terminate (handler=<optimized out>) at /tmp/deploy/objdir/../gcc-10.2.0/libstdc++-v3/libsupc++/eh_terminate.cc:48
No locals.
#7  0x00007f9f016d7b99 in __cxa_call_terminate (ue_header=ue_header@entry=0x7f9e4804a1d0) at /tmp/deploy/objdir/../gcc-10.2.0/libstdc++-v3/libsupc++/eh_call.cc:54
        xh = 0x7f9e4804a180
#8  0x00007f9f016d84d1 in __cxxabiv1::__gxx_personality_v0 (version=<optimized out>, actions=6, exception_class=5138137972254386944, ue_header=0x7f9e4804a1d0, context=<optimized out>)
    at /tmp/deploy/objdir/../gcc-10.2.0/libstdc++-v3/libsupc++/eh_personality.cc:685
        do_something = <optimized out>
        install_context = <optimized out>
        found_nothing = found_nothing
        found_terminate = found_terminate
        found_cleanup = found_cleanup
        found_handler = found_handler
        found_type = <optimized out>
        info = {Start = 140318217270272, LPStart = 140320913016168, ttype_base = 0, TType = 0x7f9e617ef3a8 "\316\364\006\001", action_table = 0x0, ttype_encoding = 206 '\316', call_site_encoding = 244 '\364'}
        language_specific_data = <optimized out>
        action_record = <optimized out>
        p = <optimized out>
        landing_pad = <optimized out>
        ip = <optimized out>
        handler_switch_value = <optimized out>
        thrown_ptr = 0x0
        foreign_exception = <optimized out>
        ip_before_insn = 0
        xh = 0x7f9e4804a180
#9  0x00007f9f022cd6df in _Unwind_RaiseException_Phase2 (exc=exc@entry=0x7f9e4804a1d0, context=context@entry=0x7f9e617ef6b0, frames_p=frames_p@entry=0x7f9e617ef7a0) at /tmp/deploy/objdir/../gcc-10.2.0/libgcc/unwind.inc:64
        fs = {regs = {reg = {{loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 18446744073709551560, 
                  offset = -56, exp = 0xffffffffffffffc8 <error: Cannot access memory at address 0xffffffffffffffc8>}, how = REG_SAVED_OFFSET}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, exp = 0x0}, 
                how = REG_UNSAVED}, {loc = {reg = 18446744073709551568, offset = -48, exp = 0xffffffffffffffd0 <error: Cannot access memory at address 0xffffffffffffffd0>}, how = REG_SAVED_OFFSET}, {loc = {reg = 0, offset = 0, exp = 0x0}, 
                how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 0, offset = 0, 
                  exp = 0x0}, how = REG_UNSAVED}, {loc = {reg = 18446744073709551576, offset = -40, exp = 0xffffffffffffffd8 <error: Cannot access memory at address 0xffffffffffffffd8>}, how = REG_SAVED_OFFSET}, {loc = {reg = 18446744073709551584, 
                  offset = -32, exp = 0xffffffffffffffe0 <error: Cannot access memory at address 0xffffffffffffffe0>}, how = REG_SAVED_OFFSET}, {loc = {reg = 18446744073709551592, offset = -24, 
                  exp = 0xffffffffffffffe8 <error: Cannot access memory at address 0xffffffffffffffe8>}, how = REG_SAVED_OFFSET}, {loc = {reg = 18446744073709551600, offset = -16, 
                  exp = 0xfffffffffffffff0 <error: Cannot access memory at address 0xfffffffffffffff0>}, how = REG_SAVED_OFFSET}, {loc = {reg = 18446744073709551608, offset = -8, 
                  exp = 0xfffffffffffffff8 <error: Cannot access memory at address 0xfffffffffffffff8>}, how = REG_SAVED_OFFSET}, {loc = {reg = 0, offset = 0, exp = 0x0}, how = REG_UNSAVED}}, prev = 0x0, cfa_offset = 160, cfa_reg = 7, cfa_exp = 0x0, 
            cfa_how = CFA_REG_OFFSET}, pc = 0x50161e <Checkpoint::~Checkpoint() [clone .cold]>, personality = 0x44f420 <__gxx_personality_v0@plt>, data_align = -8, code_align = 1, retaddr_column = 16, fde_encoding = 27 '\033', 
          lsda_encoding = 27 '\033', saw_z = 1 '\001', signal_frame = 0 '\000', eh_ptr = 0x0}
        match_handler = 4
        code = _URC_NO_REASON
        frames = 4
#10 0x00007f9f022cdd61 in _Unwind_RaiseException (exc=exc@entry=0x7f9e4804a1d0) at /tmp/deploy/objdir/../gcc-10.2.0/libgcc/unwind.inc:136
        this_context = {reg = {0x7f9e617ef928, 0x7f9e617ef930, 0x0, 0x7f9e617ef938, 0x0, 0x0, 0x7f9e617ef960, 0x0, 0x0, 0x0, 0x0, 0x0, 0x7f9e617ef940, 0x7f9e617ef948, 0x7f9e617ef950, 0x7f9e617ef958, 0x7f9e617ef968, 0x0}, cfa = 0x7f9e617ef970, 
          ra = 0x7f9f016d8da7 <__cxxabiv1::__cxa_throw(void*, std::type_info*, void (*)(void*))+55>, lsda = 0x0, bases = {tbase = 0x0, dbase = 0x0, func = 0x7f9f022cda30 <_Unwind_RaiseException>}, flags = 4611686018427387904, version = 0, 
          args_size = 0, by_value = '\000' <repeats 17 times>}
        cur_context = {reg = {0x7f9e617ef928, 0x7f9e617ef930, 0x0, 0x7f9e617ef9b8, 0x0, 0x0, 0x7f9e617ef9f8, 0x0, 0x0, 0x0, 0x0, 0x0, 0x7f9e617efa00, 0x7f9e617ef9d0, 0x7f9e617ef9d8, 0x7f9e617ef9e0, 0x7f9e617efa08, 0x0}, cfa = 0x7f9e617efa10, 
          ra = 0x50162a <Checkpoint::MemoryCounter::operator+=(unsigned long) [clone .cold]>, lsda = 0x106f4ce, bases = {tbase = 0x0, dbase = 0x0, func = 0x50161e <Checkpoint::~Checkpoint() [clone .cold]>}, flags = 4611686018427387904, version = 0, 
          args_size = 0, by_value = '\000' <repeats 17 times>}
--Type <RET> for more, q to quit, c to continue without paging--
        code = <optimized out>
        frames = 0

#11 0x00007f9f016d8da7 in __cxxabiv1::__cxa_throw (obj=<optimized out>, tinfo=0xe77718 <typeinfo for gsl::fail_fast>, dest=0x639520 <gsl::fail_fast::~fail_fast()>) at /tmp/deploy/objdir/../gcc-10.2.0/libstdc++-v3/libsupc++/eh_throw.cc:90
        globals = <optimized out>
        header = 0x7f9e4804a170
#12 0x0000000000d70665 in __cxxabiv1::__cxa_throw (thrownException=0x7f9e4804a1f0, type=0xe77718 <typeinfo for gsl::fail_fast>, destructor=<optimized out>)
    at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/experimental/exception_tracer/ExceptionTracerLib.cpp:106
        orig_cxa_throw = 0x0
#13 0x00000000004620b2 in gsl::detail::fail_fast_throw (message=0xe35f40 "GSL: Precondition failure: 'getNumCursorsInCheckpoint() == 0' at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/engines/ep/src/checkpoint.cc:102")
    at /home/couchbase/jenkins/workspace/couchbase-server-unix/third_party/gsl-lite/include/gsl/gsl-lite.hpp:1769
No locals.
#14 0x000000000050162a in Checkpoint::~Checkpoint (this=0x7f9e1b637940, __in_chrg=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/engines/ep/src/checkpoint.cc:102
        core = <optimized out>
        core = <optimized out>
        logger = <optimized out>
#15 0x00000000008d18a4 in std::default_delete<Checkpoint>::operator() (__ptr=0x7f9e1b637940, this=0x7f9e13f71510) at /opt/gcc-10.2.0/include/c++/10.2.0/bits/unique_ptr.h:79
No locals.
#16 std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >::~unique_ptr (this=0x7f9e13f71510, __in_chrg=<optimized out>) at /opt/gcc-10.2.0/include/c++/10.2.0/bits/unique_ptr.h:361
        __ptr = <error reading variable: Cannot access memory at address 0x7f9e13f71510>
#17 boost::container::allocator_traits<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> > >::priv_destroy<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> > > (p=0x7f9e13f71510) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/container/allocator_traits.hpp:403
No locals.
#18 boost::container::allocator_traits<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> > >::destroy<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> > > (p=0x7f9e13f71510, a=...) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/container/allocator_traits.hpp:331
        value = false
        flag = <optimized out>
        value = <optimized out>
        flag = <optimized out>
#19 boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false>::destructor<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> > > (a=..., this=0x7f9e13f71500)
    at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/container/detail/node_alloc_holder.hpp:142
No locals.
#20 boost::container::dtl::allocator_node_destroyer<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> > >::operator() (
    p=<optimized out>, this=<synthetic pointer>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/container/detail/destroyers.hpp:412
No locals.

#21 boost::intrusive::list_impl<boost::intrusive::bhtraits<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false>, boost::intrusive::list_node_traits<void*>, (boost::intrusive::link_mode_type)0, boost::intrusive::dft_tag, 1u>, unsigned long, true, void>::erase_and_dispose<boost::container::dtl::allocator_node_destroyer<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> > > > (disposer=..., i=..., this=0x7f9e617efac0) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/intrusive/list.hpp:677
        to_erase = 0x7f9e13f71500
#22 boost::intrusive::list_impl<boost::intrusive::bhtraits<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false>, boost::intrusive::list_node_traits<void*>, (boost::intrusive::link_mode_type)0, boost::intrusive::dft_tag, 1u>, unsigned long, true, void>::erase_and_dispose<boost::container::dtl::allocator_node_destroyer<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> > > > (disposer=..., i=..., this=0x7f9e617efac0) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/intrusive/list.hpp:684
No locals.
#23 boost::container::list<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, void>::erase (p=..., this=0x7f9e617efac0)
    at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/boost.exploded/include/boost/container/list.hpp:972
No locals.
#24 CheckpointDestroyerTask::run (this=0x7f9e11995a90) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/engines/ep/src/checkpoint_remover.cc:52
        checkpoint = {m_iit = {static stateful_value_traits = false, members_ = {nodeptr_ = 0x7f9e13f71500}}}
        temporary = {<boost::container::dtl::node_alloc_holder<boost::container::new_allocator<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> > >, boost::intrusive::list_impl<boost::intrusive::bhtraits<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false>, boost::intrusive::list_node_traits<void*>, (boost::intrusive::link_mode_type)0, boost::intrusive::dft_tag, 1>, unsigned long, true, void> >> = {<boost::container::new_allocator<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false> >> = {<No data fields>}, m_icont = {static constant_time_size = true, 
              static stateful_value_traits = <optimized out>, static has_container_from_iterator = <optimized out>, static safemode_or_autounlink = false, 
              data_ = {<boost::intrusive::bhtraits<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false>, boost::intrusive::list_node_traits<void*>, (boost::intrusive::link_mode_type)0, boost::intrusive::dft_tag, 1>> = {<boost::intrusive::bhtraits_base<boost::container::base_node<std::unique_ptr<Checkpoint, std::default_delete<Checkpoint> >, boost::container::dtl::list_hook<void*>, false>, boost::intrusive::list_node<void*>*, boost::intrusive::dft_tag, 1>> = {<No data fields>}, static link_mode = boost::intrusive::normal_link}, root_plus_size_ = {<boost::intrusive::detail::size_holder<true, unsigned long, void>> = {static constant_time_size = <optimized out>, 
                    size_ = 0}, m_header = {<boost::intrusive::list_node<void*>> = {next_ = 0x7f9e617efac8, prev_ = 0x7f9e617efac8}, <No data fields>}}}}}, <No data fields>}
#25 0x0000000000bd30bd in GlobalTask::execute (this=0x7f9e11995a90, threadName=...) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/executor/globaltask.cc:104


        guard = {previous = 0x0}
        taskableName = {value = {_M_elems = "bucket9", '\000' <repeats 24 times>}}
        executedAt = <optimized out>
        scheduleOverhead = <optimized out>
        start = <optimized out>
        runAgain = <optimized out>
        end = <optimized out>
        runtime = <optimized out>
--Type <RET> for more, q to quit, c to continue without paging--
#26 0x0000000000bd12ea in FollyExecutorPool::TaskProxy::scheduleViaCPUPool()::{lambda()#2}::operator()() const (__closure=0x7f9e617efe00) at /opt/gcc-10.2.0/include/c++/10.2.0/string_view:133
        runAgain = <optimized out>
        proxy = <error reading variable: Cannot access memory at address 0x7f9ea4770790>
        proxy = <optimized out>
        runAgain = <optimized out>
        _logger_ = <optimized out>
#27 folly::detail::function::FunctionTraits<void ()>::callSmall<FollyExecutorPool::TaskProxy::scheduleViaCPUPool()::{lambda()#2}>(folly::detail::function::Data&) (p=...)
    at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/folly.exploded/include/folly/Function.h:363
        fn = @0x7f9e617efe00: {__proxy = @0x7f9ea4770790}

#28 0x0000000000bd4256 in folly::detail::function::FunctionTraits<void ()>::operator()() (this=0x7f9e617efe00) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/folly.exploded/include/folly/Function.h:390
        fn = @0x7f9e617efe00: {<folly::detail::function::FunctionTraits<void()>> = {<No data fields>}, data_ = {big = 0x7f9ea4770790, tiny = {
              __data = "\220\aw\244\236\177\000\000\000\000\000\000\236\177\000\001", '\000' <repeats 17 times>, "\377~a\236\177\000\000\326\274\325\000\000\000\000", __align = {<No data fields>}}}, 
          call_ = 0xbd1260 <folly::detail::function::FunctionTraits<void ()>::callSmall<FollyExecutorPool::TaskProxy::scheduleViaCPUPool()::{lambda()#2}>(folly::detail::function::Data&)>, 
          exec_ = 0x5e4250 <folly::detail::function::DispatchSmallTrivial::exec_<16ul>(folly::detail::function::Op, folly::detail::function::Data*, folly::detail::function::Data*)>}
#29 operator() (__closure=<optimized out>) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/executor/cancellable_cpu_executor.cc:42
        task = {storage_ = {{emptyState = -112 '\220', value = {task = 0x7f9e11995a90, func = {<folly::detail::function::FunctionTraits<void()>> = {<No data fields>}, data_ = {big = 0x7f9ea4770790, tiny = {
                      __data = "\220\aw\244\236\177\000\000\000\000\000\000\236\177\000\001", '\000' <repeats 17 times>, "\377~a\236\177\000\000\326\274\325\000\000\000\000", __align = {<No data fields>}}}, 
                  call_ = 0xbd1260 <folly::detail::function::FunctionTraits<void ()>::callSmall<FollyExecutorPool::TaskProxy::scheduleViaCPUPool()::{lambda()#2}>(folly::detail::function::Data&)>, 
                  exec_ = 0x5e4250 <folly::detail::function::DispatchSmallTrivial::exec_<16ul>(folly::detail::function::Op, folly::detail::function::Data*, folly::detail::function::Data*)>}}}, hasValue = true}}
        this = <optimized out>
#30 0x0000000000d6c65f in folly::detail::function::FunctionTraits<void ()>::operator()() (this=0x7f9e617f00b0) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/executors/ThreadPoolExecutor.cpp:98
        fn = @0x7f9e617f00b0: {<folly::detail::function::FunctionTraits<void()>> = {<No data fields>}, data_ = {big = 0x7f9efcebfc00, tiny = {
              __data = "\000\374\353\374\236\177\000\000\000\000\000\000\000\000\000\000\030\000\000\000\000\000\000\000\020\303\031\001\000\000\000\0000\000\000\000\000\000\000\000\210F$\000\000\000\000", __align = {<No data fields>}}}, 
          call_ = 0xbd45f0 <folly::detail::function::FunctionTraits<void()>::callSmall<CancellableCPUExecutor::add(GlobalTask*, folly::Func)::<lambda()> >(folly::detail::function::Data &)>, 
          exec_ = 0x5e4250 <folly::detail::function::DispatchSmallTrivial::exec_<16ul>(folly::detail::function::Op, folly::detail::function::Data*, folly::detail::function::Data*)>}
#31 folly::ThreadPoolExecutor::runTask (this=this@entry=0x7f9efcebfd00, thread=..., task=...) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/executors/ThreadPoolExecutor.cpp:98
        rctx = {prev_ = {<std::__shared_ptr<folly::RequestContext, (__gnu_cxx::_Lock_policy)2>> = {<std::__shared_ptr_access<folly::RequestContext, (__gnu_cxx::_Lock_policy)2, false, false>> = {<No data fields>}, _M_ptr = 0x0, _M_refcount = {
                _M_pi = 0x0}}, <No data fields>}}
        startTime = {__d = {__r = 2111682576335968}}
        stats = {expired = false, waitTime = {__r = 88710}, runTime = {__r = 0}, enqueueTime = {__d = {__r = 2111682576247258}}, requestId = 0}
#32 0x0000000000d55357 in folly::CPUThreadPoolExecutor::threadRun (this=0x7f9efcebfd00, thread=...) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/executors/CPUThreadPoolExecutor.cpp:306
        task = {storage_ = {{emptyState = 0 '\000', value = {<folly::ThreadPoolExecutor::Task> = {func_ = {<folly::detail::function::FunctionTraits<void()>> = {<No data fields>}, data_ = {big = 0x7f9efcebfc00, tiny = {
                        __data = "\000\374\353\374\236\177\000\000\000\000\000\000\000\000\000\000\030\000\000\000\000\000\000\000\020\303\031\001\000\000\000\0000\000\000\000\000\000\000\000\210F$\000\000\000\000", __align = {<No data fields>}}}, 
                    call_ = 0xbd45f0 <folly::detail::function::FunctionTraits<void()>::callSmall<CancellableCPUExecutor::add(GlobalTask*, folly::Func)::<lambda()> >(folly::detail::function::Data &)>, 
                    exec_ = 0x5e4250 <folly::detail::function::DispatchSmallTrivial::exec_<16ul>(folly::detail::function::Op, folly::detail::function::Data*, folly::detail::function::Data*)>}, enqueueTime_ = {__d = {__r = 2111682576247258}}, 
                  expiration_ = {__r = 0}, expireCallback_ = {<folly::detail::function::FunctionTraits<void()>> = {<No data fields>}, data_ = {big = 0x7f9e617f0250, tiny = {
                        __data = "P\002\177a\236\177\000\000\210F$\000\000\000\000\000\210F$\000\000\000\000\000\311\267Z", '\000' <repeats 13 times>, "\322gv\001\237\177\000", __align = {<No data fields>}}}, 
                    call_ = 0x471189 <folly::detail::function::FunctionTraits<void ()>::uninitCall(folly::detail::function::Data&)>, exec_ = 0x0}, 
                  context_ = {<std::__shared_ptr<folly::RequestContext, (__gnu_cxx::_Lock_policy)2>> = {<std::__shared_ptr_access<folly::RequestContext, (__gnu_cxx::_Lock_policy)2, false, false>> = {<No data fields>}, _M_ptr = 0x0, _M_refcount = {
                        _M_pi = 0x0}}, <No data fields>}}, poison = false, priority_ = 0 '\000', queueObserverPayload_ = 0}}, hasValue = true}}
        guard = {storage_ = {{emptyState = 32 ' ', value = {list_ = {prev = 0x1224e20 <folly::emptyList>, curr = {forbid = true, allowTerminationOnBlocking = false, ex = 0x7f9efcebfd00, tag = {static npos = <optimized out>, 
                      b_ = 0x7f9efce10360 <error: Cannot access memory at address 0x7f9efce10360>, e_ = 0x7f9efce10379 <error: Cannot access memory at address 0x7f9efce10379>}}}}}, hasValue = true}}
        threadIDsGuard = {<folly::detail::ScopeGuardImplBase> = {dismissed_ = false}, function_ = {__this = 0x7f9efcebfd00}}
#33 0x0000000000d6f1fa in std::__invoke_impl<void, void (folly::ThreadPoolExecutor::*&)(std::shared_ptr<folly::ThreadPoolExecutor::Thread>), folly::ThreadPoolExecutor*&, std::shared_ptr<folly::ThreadPoolExecutor::Thread>&> (__f=<optimized out>, 
    __t=<optimized out>, __f=<optimized out>, __t=<optimized out>) at /opt/gcc-10.2.0/include/c++/10.2.0/bits/invoke.h:73
No locals.
#34 std::__invoke<void (folly::ThreadPoolExecutor::*&)(std::shared_ptr<folly::ThreadPoolExecutor::Thread>), folly::ThreadPoolExecutor*&, std::shared_ptr<folly::ThreadPoolExecutor::Thread>&> (__fn=<optimized out>)
    at /opt/gcc-10.2.0/include/c++/10.2.0/bits/invoke.h:95
No locals.
#35 std::_Bind<void (folly::ThreadPoolExecutor::*(folly::ThreadPoolExecutor*, std::shared_ptr<folly::ThreadPoolExecutor::Thread>))(std::shared_ptr<folly::ThreadPoolExecutor::Thread>)>::__call<void, , 0ul, 1ul>(std::tuple<>&&, std::_Index_tuple<0ul, 1ul>) (__args=..., this=<optimized out>) at /opt/gcc-10.2.0/include/c++/10.2.0/functional:416
No locals.
#36 std::_Bind<void (folly::ThreadPoolExecutor::*(folly::ThreadPoolExecutor*, std::shared_ptr<folly::ThreadPoolExecutor::Thread>))(std::shared_ptr<folly::ThreadPoolExecutor::Thread>)>::operator()<, void>() (this=<optimized out>)
    at /opt/gcc-10.2.0/include/c++/10.2.0/functional:499
No locals.
#37 folly::detail::function::FunctionTraits<void ()>::callSmall<std::_Bind<void (folly::ThreadPoolExecutor::*(folly::ThreadPoolExecutor*, std::shared_ptr<folly::ThreadPoolExecutor::Thread>))(std::shared_ptr<folly::ThreadPoolExecutor::Thread>)> >(folly::detail::function::Data&) (p=...) at /home/couchbase/jenkins/cbdeps-ws/deps/packages/build/folly/folly-prefix/src/folly/folly/Function.h:363
        fn = <optimized out>
#38 0x0000000000bcd4f4 in folly::detail::function::FunctionTraits<void ()>::operator()() (this=0x7f9efcd2c800) at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/folly.exploded/include/folly/Function.h:390
        fn = <error reading variable: Cannot access memory at address 0x7f9efcd2c800>
#39 CBRegisteredThreadFactory::newThread(folly::Function<void ()>&&)::{lambda()#1}::operator()() (__closure=0x7f9efcd2c800) at /home/couchbase/jenkins/workspace/couchbase-server-unix/kv_engine/executor/folly_executorpool.cc:49
        threadNameOpt = {storage_ = {{emptyState = 32 ' ', value = {static npos = 18446744073709551615, _M_dataplus = {<std::allocator<char>> = {<__gnu_cxx::new_allocator<char>> = {<No data fields>}, <No data fields>}, 
                  _M_p = 0x7f9e617f0220 "NonIoPool1"}, _M_string_length = 10, {_M_local_buf = "NonIoPool1\000=[\214\005\264", _M_allocated_capacity = 8029725099528449870}}}, hasValue = true}}
        func = <error reading variable func (Cannot access memory at address 0x7f9efcd2c800)>
        func = <optimized out>
--Type <RET> for more, q to quit, c to continue without paging--
        threadNameOpt = <optimized out>
#40 folly::detail::function::FunctionTraits<void ()>::callBig<CBRegisteredThreadFactory::newThread(folly::Function<void ()>&&)::{lambda()#1}>(folly::detail::function::Data&) (p=...)
    at /home/couchbase/jenkins/workspace/couchbase-server-unix/server_build/tlm/deps/folly.exploded/include/folly/Function.h:377
        fn = <error reading variable: Cannot access memory at address 0x7f9efcd2c800>
#41 0x00007f9f01701f00 in std::execute_native_thread_routine (__p=0x7f9efcf75630) at /tmp/deploy/objdir/../gcc-10.2.0/libstdc++-v3/src/c++11/thread.cc:80
        __t = <optimized out>
#42 0x00007f9f012a8044 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
        ret = <optimized out>
        pd = <optimized out>
        out = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140318217316032, 4341741678353251457, -40176, 0, 140720786892032, 140318208925696, -4360551019101225855, -4359777624763728767}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {
              prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = <optimized out>
#43 0x00007f9f013285fc in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81
No locals.
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