Comment 6 for bug 1291299

I have not ALTERed or CREATed such tables during backup.

Backup process takes a long time and there is a small possibility that any user or script made such things. But
1. I reproduced bug any time when I took it. (it is incredible that each time someone ALTERed or CREATed tables and I don't know about it)
2. I made a partial backup with small table. ( http://www.percona.com/doc/percona-xtrabackup/2.1/innobackupex/partial_backups_innobackupex.html ) It took small amount of time. During this time tables is not ALTERed or CREATED

bt for case 2:
#0 0x00007f002ae74670 in __strrchr_sse42 () from /lib64/libc.so.6
#1 0x00000000005cae90 in strrchr (data_dir_path=0x0, tablename=0x7f00191a7440 "berg/#sql-7781_232117", extention=0x9eb461 "ibd") at /usr/include/string.h:251
#2 os_file_make_remote_pathname (data_dir_path=0x0, tablename=0x7f00191a7440 "berg/#sql-7781_232117", extention=0x9eb461 "ibd")
    at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/os/os0file.cc:3277
#3 0x00000000004d72c3 in fil_create_new_single_table_tablespace (space_id=4964, tablename=0x7f00191a7440 "berg/#sql-7781_232117", dir_path=<value optimized out>,
    flags=1024, flags2=<value optimized out>, size=4) at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/fil/fil0fil.cc:3369
#4 0x00000000004d7a89 in fil_op_log_parse_or_replay (ptr=0x7f00191a7456 "\035\223d\001\033\223d\001\037\035\223d", end_ptr=<value optimized out>,
    type=<value optimized out>, space_id=4964, log_flags=<value optimized out>)
    at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/fil/fil0fil.cc:2406
#5 0x0000000000490b9b in recv_parse_log_recs (available_memory=88080384, store_to_hash=1, buf=<value optimized out>, len=<value optimized out>,
    start_lsn=<value optimized out>, contiguous_lsn=<value optimized out>, group_scanned_lsn=0x7fff3d9f9fd8)
    at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/log/log0recv.cc:2508
#6 recv_scan_log_recs (available_memory=88080384, store_to_hash=1, buf=<value optimized out>, len=<value optimized out>, start_lsn=<value optimized out>,
    contiguous_lsn=<value optimized out>, group_scanned_lsn=0x7fff3d9f9fd8)
    at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/log/log0recv.cc:2963
#7 0x0000000000491884 in recv_group_scan_log_recs (type=78656949, limit_lsn=18446744073709551615, min_flushed_lsn=1222941760714, max_flushed_lsn=1222941760714)
    at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/log/log0recv.cc:3023
#8 recv_recovery_from_checkpoint_start_func (type=78656949, limit_lsn=18446744073709551615, min_flushed_lsn=1222941760714, max_flushed_lsn=1222941760714)
    at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/log/log0recv.cc:3315
#9 0x00000000004bf0fb in innobase_start_or_create_for_mysql () at /usr/src/debug/percona-xtrabackup-2.1.8/mysql-5.6/storage/innobase/srv/srv0start.cc:2363
#10 0x00000000004553ab in innodb_init () at xtrabackup.cc:1438
#11 xtrabackup_prepare_func () at xtrabackup.cc:5455
#12 0x000000000045777b in main (argc=0, argv=0x19c4350) at xtrabackup.cc:6035