How can I diagnose this issue?
I've tried using strace and I see the following that seems to be stuck in a loop:
recvfrom(5, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 567516, 0, NULL, NULL) = 567516
--- SIGIO {si_signo=SIGIO, si_code=SI_KERNEL} ---
rt_sigreturn({mask=[]}) = 567516
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
brk(0x39f4000) = 0x39f4000
brk(0x3873000) = 0x3873000
poll([{fd=5, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=5, revents=POLLOUT}])
writev(5, [{iov_base=".\0\2\0\273\2\340\3-\0\22\0\274\2\340\0039\0-a-misc-cinzel"..., iov_len=88}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 88
poll([{fd=5, events=POLLIN}], 1, -1) = 1 ([{fd=5, revents=POLLIN}])
--- SIGIO {si_signo=SIGIO, si_code=SI_KERNEL} ---
rt_sigreturn({mask=[]}) = 1
recvmsg(5, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\0\330\tO\0\3\0\377\377\0\0\0\0\20\0\5\0\0\0\0\0\0\0\4\0\23\0\23\0\20\0"..., iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 4096
brk(0x3934000) = 0x3934000
recvfrom(5, "\0\0\0\0\0\0\0\0\1\0\v\0\v\0\20\0\5\0{*\0\0\t\0\t\0\20\0\5\0P$"..., 782684, 0, NULL, NULL) = 782684
--- SIGIO {si_signo=SIGIO, si_code=SI_KERNEL} ---
rt_sigreturn({mask=[]}) = 782684
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
brk(0x39f4000) = 0x39f4000
brk(0x3873000) = 0x3873000
poll([{fd=5, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=5, revents=POLLOUT}])
writev(5, [{iov_base=".\0\2\0\274\2\340\3-\0\24\0\275\2\340\3D\0-a-misc-cinzel"..., iov_len=96}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 96
poll([{fd=5, events=POLLIN}], 1, -1) = 1 ([{fd=5, revents=POLLIN}])
--- SIGIO {si_signo=SIGIO, si_code=SI_KERNEL} ---
rt_sigreturn({mask=[]}) = 1
recvmsg(5, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\0\333\tO\0\3\0\372\377\0\0\0\0\20\0\6\0\0\0\0\0\0\0\4\0\26\0\26\0\20\0"..., iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 4096
brk(0x3934000) = 0x3934000
recvfrom(5, "\0\0\0\0\0\0\0\0\1\0\7\0\7\0\20\0\6\0\375\34\1\0\v\0\v\0\20\0\6\0{*"..., 782684, 0, NULL, NULL) = 782684
--- SIGIO {si_signo=SIGIO, si_code=SI_KERNEL} ---
rt_sigreturn({mask=[]}) = 782684
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(5, {msg_namelen=0}, 0) = -1 EAGAIN (Resource temporarily unavailable)
brk(0x39f4000) = 0x39f4000
brk(0x3873000) = 0x3873000
poll([{fd=5, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=5, revents=POLLOUT}])
writev(5, [{iov_base=".\0\2\0\275\2\340\3-\0\23\0\276\2\340\3=\0-a-misc-cinzel"..., iov_len=92}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 92
poll([{fd=5, events=POLLIN}], 1, -1strace: Process 12237 detached