[Magma] - memcached crashing from /diag/eval params change

curl -i -u Administrator:password --data 'ns_bucket:update_bucket_props("magma",[{extra_config_string, "backend=magma;cursor_dropping_checkpoint_mem_upper_mark=100;max_num_shards=64;magma_num_flushers=32;magma_num_compactors=64"}]).' http://localhost:8091/diag/eval

Service 'memcached' exited with status 134. Restarting. Messages: 2020-01-24T15:37:14.121598+00:00 CRITICAL /opt/couchbase/bin/memcached() [0x400000+0x145e02] 2020-01-24T15:37:14.121616+00:00 CRITICAL /opt/couchbase/bin/../lib/libstdc++.so.6() [0x7f226acab000+0x8ef86] 2020-01-24T15:37:14.121637+00:00 CRITICAL /opt/couchbase/bin/../lib/libstdc++.so.6() [0x7f226acab000+0x8efd1] 2020-01-24T15:37:14.121652+00:00 CRITICAL /opt/couchbase/bin/../lib/libstdc++.so.6() [0x7f226acab000+0x8f213] 2020-01-24T15:37:14.121666+00:00 CRITICAL /opt/couchbase/bin/../lib/../lib/ep.so() [0x7f226530a000+0x1abfc1] 2020-01-24T15:37:14.121673+00:00 CRITICAL /opt/couchbase/bin/../lib/../lib/ep.so() [0x7f226530a000+0x1b7e10] 2020-01-24T15:37:14.121680+00:00 CRITICAL /opt/couchbase/bin/../lib/../lib/ep.so() [0x7f226530a000+0x12c614] 2020-01-24T15:37:14.121689+00:00 CRITICAL /opt/couchbase/bin/../lib/libplatform_so.so.0.1.0() [0x7f226cb54000+0x8ee7] 2020-01-24T15:37:14.121694+00:00 CRITICAL /lib64/libpthread.so.0() [0x7f226a576000+0x7e65] 2020-01-24T15:37:14.121723+00:00 CRITICAL /lib64/libc.so.6(clone+0x6d) [0x7f226a1a8000+0xfe88d]