Setting a low TotalUmMemory causes PrimProc to crash on any request.

$ mariadb -e 'select * from t' test

+------+------+

| a    | b    |

+------+------+

|   17 |   42 |

|    1 |    2 |

|    1 |    3 |

+------+------+

$ sudo mcsSetConfig HashJoin TotalUmMemory 256M

$ sudo systemctl restart mcs-primproc.service

$ mariadb -e 'select * from t' test

--------------

select * from t

--------------

ERROR 1815 (HY000) at line 1: Internal error: MCS-2004: Cannot connect to ExeMgr.

Thread 99 "HJSBigSide" received signal SIGSEGV, Segmentation fault.

[Switching to Thread 0x7c9507fff6c0 (LWP 482752)]

0x00007c99da108054 in joiner::TupleJoiner::isFinished (this=0x0) at MariaDBEnterprise/storage/columnstore/columnstore/utils/joiner/tuplejoiner.h:466

466         return finished;

(gdb) bt

#0  0x00007c99da108054 in joiner::TupleJoiner::isFinished (this=0x0) at MariaDBEnterprise/storage/columnstore/columnstore/utils/joiner/tuplejoiner.h:466

#1  0x00007c99da105d94 in joblist::TupleHashJoinStep::segregateJoiners (this=0x7c95080f6420)

    at MariaDBEnterprise/storage/columnstore/columnstore/dbcon/joblist/tuplehashjoin.cpp:1935

#2  0x00007c99da0fd65d in joblist::TupleHashJoinStep::hjRunner (this=0x7c95080f6420)

    at MariaDBEnterprise/storage/columnstore/columnstore/dbcon/joblist/tuplehashjoin.cpp:689

#3  0x00007c99da108176 in joblist::TupleHashJoinStep::HJRunner::operator() (this=0x7c950801e580)

    at MariaDBEnterprise/storage/columnstore/columnstore/dbcon/joblist/tuplehashjoin.h:472

#4  0x00007c99da10d2f6 in boost::detail::function::void_function_obj_invoker<joblist::TupleHashJoinStep::HJRunner, void>::invoke (function_obj_ptr=...)

    at MariaDBEnterprise/bb/storage/columnstore/columnstore/.boost/boost-lib/include/boost/function/function_template.hpp:100

#5  0x00007c99d86db237 in boost::function_n<void>::operator() (this=0x7c950801e578)

    at MariaDBEnterprise/bb/storage/columnstore/columnstore/.boost/boost-lib/include/boost/function/function_template.hpp:789

#6  0x00007c99d86d8a68 in threadpool::ThreadPool::beginThread (this=0x5fd145f92660 <joblist::JobStep::jobstepThreadPool>)

    at MariaDBEnterprise/storage/columnstore/columnstore/utils/threadpool/threadpool.cpp:382

#7  0x00007c99d86da88f in threadpool::ThreadPool::beginThreadFunc::operator() (this=0x7c950801a558)

    at MariaDBEnterprise/storage/columnstore/columnstore/utils/threadpool/threadpool.h:326

#8  0x00007c99d86de572 in boost::detail::thread_data<threadpool::ThreadPool::beginThreadFunc>::run (this=0x7c950801a420)

    at MariaDBEnterprise/bb/storage/columnstore/columnstore/.boost/boost-lib/include/boost/thread/detail/thread.hpp:120

#9  0x00007c99d8e4b332 in thread_proxy () from /lib/x86_64-linux-gnu/librwlock.so

#10 0x00007c99d74a27f1 in start_thread (arg=<optimised out>) at ./nptl/pthread_create.c:448

#11 0x00007c99d7533c9c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78