failure in shm_ib/test_ucp_rma.nonblocking_stream_put_nb_flush_worker/0

[brminich]

happened here: https://gist.githubusercontent.com/mellanox-github/68d7ce1d0cbfc98832dffbd46886b82c/raw/0844c14c35921269c566982313a5aa0b397109f5/hpc-arm-cavium-jenkins_W0

[----------] 11 tests from shm_ib/test_ucp_rma
[ RUN      ] shm_ib/test_ucp_rma.nonblocking_stream_put_nb_flush_worker/0 <shm,ib>
/scrap/jenkins/workspace/hpc-ucx-pr/label/hpc-arm-cavium-jenkins/worker/0/contrib/../test/gtest/ucp/test_ucp_memheap.cc:121: Failure
Value of: std::string(ptr, expected_data[i].length()).substr(0, 20)
  Actual: "\0\0\0\0\x3\0\x2\0\0\0\0\0\0\0\0\0\0\0\0\0"
Expected: expected_data[i].substr(0, 20)
Which is: "\xB8\xAA\x81h\0\0\0\0A\xAB\x10\x15\x4\0\0\0\x9B\xB0\xA6\xD2"
0xffffb50c52a1
[  FAILED  ] shm_ib/test_ucp_rma.nonblocking_stream_put_nb_flush_worker/0, where GetParam() = shm,ib (333 ms)
[ RUN      ] shm_ib/test_ucp_rma.nonblocking_put_nb_flush_worker/0 <shm,ib>
[       OK ] shm_ib/test_ucp_rma.nonblocking_put_nb_flush_worker/0 (383 ms)

[brminich]

07:49:59 [ RUN      ] shm_ib/test_ucp_rma.nonblocking_stream_put_nb_flush_worker/0 <shm,ib>
07:49:59 /scrap/jenkins/workspace/hpc-ucx-pr-2/label/hpc-arm-cavium-jenkins/worker/0/contrib/../test/gtest/ucp/test_ucp_memheap.cc:121: Failure
07:49:59 Value of: std::string(ptr, expected_data[i].length()).substr(0, 20)
07:49:59   Actual: "\0\0\0\0\x3\0\x2\0\0\0\0\0\0\0\0\0\0\0\0\0"
07:49:59 Expected: expected_data[i].substr(0, 20)
07:49:59 Which is: "I\x9B\xC3y\0\0\0\0\xEB\x10\xA4\xC1\x4\0\0\0?\xA9h\x90"
07:49:59 0xffffb4f6b801
07:49:59 
[  FAILED  ] shm_ib/test_ucp_rma.nonblocking_stream_put_nb_flush_worker/0, where GetParam() = shm,ib (368 ms)

http://hpc-master.lab.mtl.com:8080/job/hpc-ucx-pr/15084/label=hpc-arm-cavium-jenkins,worker=0/consoleFull#-853622487b816df86-9afc-46eb-984f-1a9a125d73bb

[yosefe]

seems related to #4620