Program received signal SIGUSR1, User defined signal 1.
0x00007f12334039b3 in __epoll_wait_nocancel () at ../sysdeps/unix/syscall-template.S:84
84	in ../sysdeps/unix/syscall-template.S
Continuing.

Program received signal SIGUSR1, User defined signal 1.
0x00007f12334039b3 in __epoll_wait_nocancel () at ../sysdeps/unix/syscall-template.S:84
84	in ../sysdeps/unix/syscall-template.S
#0  0x00007f12334039b3 in __epoll_wait_nocancel () at ../sysdeps/unix/syscall-template.S:84
#1  0x00005564bcaccd01 in WaitEventSetWaitBlock (nevents=1, occurred_events=0x7ffce2d47e90, cur_timeout=200, set=0x5564beab53a8) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/storage/ipc/latch.c:1048
#2  WaitEventSetWait (set=set@entry=0x5564beab53a8, timeout=timeout@entry=200, occurred_events=occurred_events@entry=0x7ffce2d47e90, nevents=nevents@entry=1, wait_event_info=wait_event_info@entry=83886093) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/storage/ipc/latch.c:1000
#3  0x00005564bcacd174 in WaitLatchOrSocket (latch=0x7f1227241be4, wakeEvents=wakeEvents@entry=25, sock=sock@entry=-1, timeout=200, wait_event_info=wait_event_info@entry=83886093) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/storage/ipc/latch.c:385
#4  0x00005564bcacd225 in WaitLatch (latch=<optimized out>, wakeEvents=wakeEvents@entry=25, timeout=<optimized out>, wait_event_info=wait_event_info@entry=83886093) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/storage/ipc/latch.c:339
#5  0x00005564bca8193f in WalWriterMain () at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/postmaster/walwriter.c:293
#6  0x00005564bc8c0401 in AuxiliaryProcessMain (argc=argc@entry=2, argv=argv@entry=0x7ffce2d48070) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/bootstrap/bootstrap.c:442
#7  0x00005564bca7cd83 in StartChildProcess (type=WalWriterProcess) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/postmaster/postmaster.c:5313
#8  0x00005564bca7e11a in reaper (postgres_signal_arg=<optimized out>) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/postmaster/postmaster.c:2871
#9  <signal handler called>
#10 0x00007f12333f9573 in __select_nocancel () at ../sysdeps/unix/syscall-template.S:84
#11 0x00005564bc82a489 in ServerLoop () at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/postmaster/postmaster.c:1717
#12 0x00005564bca7fa6b in PostmasterMain (argc=5, argv=<optimized out>) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/postmaster/postmaster.c:1361
#13 0x00005564bc82c2d5 in main (argc=5, argv=0x5564bea7a850) at /build/postgresql-10-YNofMT/postgresql-10-10.0/build/../src/backend/main/main.c:228