stracing monitord process gives me this:
[pid 10724] clock_gettime(CLOCK_REALTIME, {tv_sec=1593426551, tv_nsec=127675185}) = 0
[pid 10724] futex(0x7ffd4e9be670, FUTEX_WAKE_PRIVATE, 1) = 0
[pid 10724] futex(0x7ffd4e9be6a4, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, 7, {tv_sec=1593426566, tv_nsec=127675185}, 0xffffffff <unfinished ...>
[pid 10634] <... read resumed>"UPDATE_HOST - 2 0 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"..., 2047) = 1423
[pid 10634] read(0, <unfinished ...>
[pid 10724] <... futex resumed>) = -1 ETIMEDOUT (Connection timed out)
[pid 10724] clock_gettime(CLOCK_REALTIME, {tv_sec=1593426566, tv_nsec=128045580}) = 0
[pid 10724] sendto(34, "=\0\0\0\3DELETE FROM host_monitoring WHERE last_mon_time < 1593383366", 65, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = 65
[pid 10724] recvfrom(34, "\7\0\0\1\0\0\0\"\0\0\0", 16384, MSG_DONTWAIT, NULL, NULL) = 11
[pid 10724] sendto(35, "7\0\0\0\3DELETE FROM vm_monitoring WHERE last_poll < 1593383366", 59, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = 59
[pid 10724] recvfrom(35, "\7\0\0\1\0\0\0\"\0\0\0", 16384, MSG_DONTWAIT, NULL, NULL) = 11
[pid 10724] clock_gettime(CLOCK_REALTIME, {tv_sec=1593426566, tv_nsec=129493222}) = 0
or
[pid 13619] recvfrom(35, "\7\0\0\1\0\0\0\"\0\0\0", 16384, MSG_DONTWAIT, NULL, NULL) = 11
[pid 13619] sendto(36, "7\0\0\0\3DELETE FROM vm_monitoring WHERE last_poll < 1593383825", 59, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = 59
[pid 13619] recvfrom(36, 0x5615edfb41f0, 16384, MSG_DONTWAIT, NULL, NULL) = -1 EAGAIN (Resource temporarily unavailable)
[pid 13619] poll([{fd=36, events=POLLIN}], 1, -1) = 1 ([{fd=36, revents=POLLIN}])
[pid 13619] recvfrom(36, "\7\0\0\1\0\0\0\"\0\0\0", 16384, MSG_DONTWAIT, NULL, NULL) = 11
[pid 13619] clock_gettime(CLOCK_REALTIME, {tv_sec=1593427025, tv_nsec=57558218}) = 0
Is it a timeout from the Mysql DB connection ?
Best regards,
Edouard