$ journalctl _COMM=lvmetad|tail -2
-- Reboot --
sept. 05 09:26:18 data-dev4 lvmetad[372]: Cannot lock lockfile [/run/lvmetad.pid], error was [Resource temporarily unavailable]


$ ps -aux|grep l[v]m
root        60  0.0  0.0 160440   444 ?        Ssl  09:26   0:00 lvmetad
root       117  0.0  0.0  25924  5064 ?        Ss   09:26   0:00 (lvm2)       pvscan --background --cache --activate ay --major 8 --minor 21
root       355  0.0  0.0  27280  3832 ?        Ss   09:26   0:00 /usr/bin/lvm pvscan --cache --activate ay 8:5
root       423  0.0  0.0  27280  3692 ?        Ss   09:26   0:00 /usr/bin/lvm pvscan --cache --activate ay 8:21
$ for i in 60 117 355 423 ; do ps -o lstart= -p $i ; done
Fri Sep  5 09:26:15 2014
Fri Sep  5 09:26:16 2014
Fri Sep  5 09:26:18 2014
Fri Sep  5 09:26:20 2014


$ cat /usr/lib/systemd/system/lvm2-lvmetad.service
[Unit]
Description=LVM2 metadata daemon
Documentation=man:lvmetad(8)
Requires=lvm2-lvmetad.socket
After=lvm2-lvmetad.socket
DefaultDependencies=no
Conflicts=shutdown.target

[Service]
Type=simple
NonBlocking=true
ExecStart=/usr/bin/lvmetad -f
Environment=SD_ACTIVATION=1
Restart=on-abort
PIDFile=/run/lvmetad.pid

[Install]
WantedBy=sysinit.target



*********
Debug trace:

(gdb) attach 60
Attaching to program: /usr/bin/lvmetad, process 60
warning: .dynamic section for "/usr/lib/libdevmapper.so.1.02" is not at the expected address (wrong library or version mismatch?)
warning: Could not load shared library symbols for linux-vdso.so.1.
Do you need "set solib-search-path" or "set sysroot"?
Reading symbols from /usr/lib/libdevmapper.so.1.02...done.
Loaded symbols for /usr/lib/libdevmapper.so.1.02
Reading symbols from /usr/lib/libpthread.so.0...(no debugging symbols found)...done.
[New LWP 118]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Loaded symbols for /usr/lib/libpthread.so.0
Reading symbols from /usr/lib/libc.so.6...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libc.so.6
Reading symbols from /usr/lib/libudev.so.1...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libudev.so.1
Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols found)...done.
Loaded symbols for /lib64/ld-linux-x86-64.so.2
Reading symbols from /usr/lib/librt.so.1...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/librt.so.1
Reading symbols from /usr/lib/libdl.so.2...(no debugging symbols found)...done.
Loaded symbols for /usr/lib/libdl.so.2
Got object file from memory but can't read symbols: File truncated.
0x00007f493238d565 in pthread_join () from /usr/lib/libpthread.so.0
(gdb) bt full
#0  0x00007f493238d565 in pthread_join () from /usr/lib/libpthread.so.0
No symbol table info available.
#1  0x00007f4932a12c32 in reap (waiting=waiting@entry=1, s=...) at daemon-server.c:500
        last = 0x7ffff81faf00
        ts = 0x7f4932cdbb10
        rv = 0x0
#2  0x00007f4932a13b8d in daemon_start (s=...) at daemon-server.c:593
        failed = <optimized out>
        _log = {log_config = {1, 1, 0 <repeats 30 times>}, backend_state = {0x0 <repeats 32 times>}, name = 0x7f4932a1599f "lvmetad"}
        _threads = {s = {thread_stack_size = 0, avoid_oom = 0, foreground = 0, name = 0x0, pidfile = 0x0, socket_path = 0x0, protocol = 0x0,
            protocol_version = 0, handler = 0x0, daemon_init = 0x0, daemon_fini = 0x0, socket_fd = 0, log = 0x0, threads = 0x0, private = 0x0}, client = {
            socket_fd = 0, thread_id = 0, read_buf = 0x0, private = 0x0}, next = 0x7f4932cdbb10, active = 0}
#3  0x00007f4932a0fe2b in main (argc=1, argv=0x7ffff81fb4f8) at lvmetad-core.c:1254
        opt = <optimized out>
        ls = {log = 0x7ffff81fafa0, log_config = 0x7f4932a1588a "", pvid_to_pvmeta = 0x7f4924004d50, device_to_pvid = 0x7f4924004e80,
          vgid_to_metadata = 0x7f4924004fb0, vgid_to_vgname = 0x7f49240050e0, vgname_to_vgid = 0x7f4924005340, pvid_to_vgid = 0x7f4924005210, lock = {
            vg = 0x7f4932cdb7c0, vg_lock_map = {__data = {__lock = 0, __count = 0, __owner = 0, __nusers = 0, __kind = 0, __spins = 0, __elision = 0,
                __list = {__prev = 0x0, __next = 0x0}}, __size = '\000' <repeats 39 times>, __align = 0}, pvid_to_pvmeta = {__data = {__lock = 0,
                __count = 0, __owner = 0, __nusers = 0, __kind = 1, __spins = 0, __elision = 0, __list = {__prev = 0x0, __next = 0x0}},
              __size = '\000' <repeats 16 times>, "\001", '\000' <repeats 22 times>, __align = 0}, vgid_to_metadata = {__data = {__lock = 0, __count = 0,
                __owner = 0, __nusers = 0, __kind = 1, __spins = 0, __elision = 0, __list = {__prev = 0x0, __next = 0x0}},
              __size = '\000' <repeats 16 times>, "\001", '\000' <repeats 22 times>, __align = 0}, pvid_to_vgid = {__data = {__lock = 0, __count = 0,
                __owner = 0, __nusers = 0, __kind = 0, __spins = 0, __elision = 0, __list = {__prev = 0x0, __next = 0x0}},
              __size = '\000' <repeats 39 times>, __align = 0}}, token = "filter:0", '\000' <repeats 119 times>, token_lock = {__data = {__lock = 0,
              __count = 0, __owner = 0, __nusers = 0, __kind = 0, __spins = 0, __elision = 0, __list = {__prev = 0x0, __next = 0x0}},
            __size = '\000' <repeats 39 times>, __align = 0}}
        s = {thread_stack_size = 0, avoid_oom = 0, foreground = 0, name = 0x7f4932a1599f "lvmetad", pidfile = 0x7f4932a15976 "/run/lvmetad.pid",
          socket_path = 0x7f4932a15987 "/run/lvm/lvmetad.socket", protocol = 0x7f4932a1599f "lvmetad", protocol_version = 1,
          handler = 0x7f4932a11460 <handler>, daemon_init = 0x7f4932a10190 <init>, daemon_fini = 0x7f4932a10090 <fini>, socket_fd = 0, log = 0x0,
          threads = 0x0, private = 0x7ffff81fb250}
(gdb) thread 2
[Switching to thread 2 (Thread 0x7f49313c9700 (LWP 118))]
#0  0x00007f493239366d in read () from /usr/lib/libpthread.so.0
(gdb) bt full
#0  0x00007f493239366d in read () from /usr/lib/libpthread.so.0
No symbol table info available.
#1  0x00007f4932a14786 in buffer_read (fd=6, buffer=0x7f49313c8e98) at daemon-io.c:38
        result = <optimized out>
#2  0x00007f4932a12f97 in client_thread (state=0x7f4932cdbb10) at daemon-server.c:421
        req = {cft = 0x7f4924005490, buffer = {allocated = 32, used = 0, mem = 0x7f4924001300 "\250"}}
        res = {error = 0, cft = 0x7f49240114c0, buffer = {allocated = 0, used = 0, mem = 0x0}}
#3  0x00007f493238c124 in start_thread () from /usr/lib/libpthread.so.0
No symbol table info available.
#4  0x00007f49320c04bd in clone () from /usr/lib/libc.so.6
No symbol table info available.
(gdb) detach
Detaching from program: /usr/bin/lvmetad, process 60
(gdb) quit