xtrabackup_55 gets stuck not under root

[Vadim Tkachenko]

when I start innobackupex under 'mysql' user,
the process xtrabackup_55 gets stuck in loop

>> log scanned up to (77776005026)
>> log scanned up to (77776005026)
>> log scanned up to (77776005026)
>> log scanned up to (77776005026)
>> log scanned up to (77776005026)
>> log scanned up to (77776005026)

gdb bt for xtrabackup_55 is

(gdb) bt
#0 0x00000038868ac3bd in nanosleep () from /lib64/libc.so.6
#1 0x00000038868e1574 in usleep () from /lib64/libc.so.6
#2 0x00000000004100a1 in xtrabackup_backup_func () at xtrabackup.c:4655
#3 0x0000000000414259 in main (argc=0, argv=0x1ecf4a0) at xtrabackup.c:7132

Strange thing is that this does not happen when I run innobackupex as 'root'

[Vadim Tkachenko (vadim-tk)]

and command I am running is
innobackupex --galera-info --tmpdir=/tmp --stream=tar --defaults-file=/etc/my.cnf --socket=/tmp/mysql.sock /tmp

[Vadim Tkachenko (vadim-tk)]

the problem there is that file "/tmp/xtrabackup_suspended" is left from previous unsuccessful run,
and it broke whole innobackupex logic.
we need to clean these files at the start (and make sure there is no other process running at the same time)

[Vadim Tkachenko (vadim-tk)]

ok, so it is duplicate of https://bugs.launchpad.net/percona-xtrabackup/+bug/1007446