Maxscale dump in RoutingWorker::execute_concurrently

The maxscale process failed with the following backtrace.

This is the performance issue. The one maxscale is capable up to 5k connections. Over the 5k connection, the response is quite slow .. and after few minutes the maxscale crash.

2023-11-21 11:57:17 alert : MaxScale 22.08.4 received fatal signal 6. Commit ID: 9be47263ae2ff2c7bdf4c3d1334fb86a7de53b77 System name: Li
nux Release string: undefined
2023-11-21 11:57:17 alert : Statement currently being classified: none/unknown
2023-11-21 11:57:17 notice : For a more detailed stacktrace, install GDB and add 'debug=gdb-stacktrace' under the [maxscale] section.
nm: /lib/x86_64-linux-gnu/libc.so.6: no symbols
/lib/x86_64-linux-gnu/libpthread.so.0(+0x11174): ??:?
/lib/x86_64-linux-gnu/libpthread.so.0(+0x11278): ??:?
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN8maxscale13RoutingWorker20execute_concurrentlyERKSt8functionIFvvEE+0x52)
: maxutils/maxbase/include/maxbase/semaphore.hh:146
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN8maxscale12WorkerGlobalISt13unordered_mapIjmSt4hashIjESt8equal_toIjESaIS
t4pairIKjmEEEE6assignERKSA_0xdb): /usr/include/c+/10/bits/std_function.h:244
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(0x2ae40d): /usr/include/c+/10/bits/hashtable.h:421
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker14handle_messageERNS_12MessageQueueERKNS_19MessageQueueMessageE+0x79): maxutils/maxbase/src/worker.cc:738
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase17EventMessageQueue18handle_poll_eventsEPNS_6WorkerEjNS_8Pollable7ContextE+0x73): maxutils/maxbase/src/messagequeue.cc:220
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker14deliver_eventsEmNSt6chrono10time_pointINS1_3_V212steady_clockENS1_8durationIlSt5ratioILl1ELl1000000000EEEEEEPNS_8PollableEjNSA_7ContextE+0x8d): maxutils/maxbase/src/worker.cc:1043
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker15poll_waiteventsEv+0x344): maxutils/maxbase/src/worker.cc:1168
/usr/lib/x86_64-linux-gnu/maxscale/libmaxscale-common.so.1.0.0(_ZN7maxbase6Worker3runEPNS_9SemaphoreE+0x4f): maxutils/maxbase/src/worker.cc:822
/usr/bin/maxscale(main+0x26fd): server/core/gateway.cc:2243
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xea): ??:0
/usr/bin/maxscale(_start+0x2a): ??:?
alert : Writing core dump.

The current maxscale configuration

[maxscale]

threads=auto

[db1]

type=server

address=db-1

port=3306

protocol=MariaDBBackend

[db2]

type=server

address=db-2

port=3306

protocol=MariaDBBackend

[db3]

type=server

address=db-3

port=3306

protocol=MariaDBBackend

[Read-Write-Service]

type=service

router=readwritesplit

servers=db1,db2,db3

user=maxscale

password=<redacted>

connection_keepalive=300s

master_accept_reads=true

max_slave_replication_lag=2s

filters=Hint

[Read-Write-Listener]

type=listener

service=Read-Write-Service

protocol=MariaDBClient

port=3306