Comment 8 for bug 917823

Same here:

- InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy and Percona Inc 2009-2012. All Rights Reserved.
- xtrabackup_55 version 2.0.1 for Percona Server 5.5.16 Linux (x86_64) (revision id: 446)
- MySQL-Server version: 5.5.24-55-log Percona Server (GPL), Release rel26.0, Revision 256
- act as a slave
- Datadir ~81GB

.
.
.
xtrabackup: error: log block numbers mismatch:
xtrabackup: error: expected log block no. 537104441, but got no. 537124913 from the log file.
xtrabackup: error: it looks like InnoDB log has wrapped around before xtrabackup could process all records due to either log copying being too slow, or log files being too small.
xtrabackup: Error: xtrabackup_copy_logfile() failed.

.
.
.
xtrabackup: The latest check point (for incremental): '1374609880770'
xtrabackup: Stopping log copying thread.

xtrabackup: Error: log_copying_thread failed.
120719 12:55:21 innobackupex: All tables unlocked
120719 12:55:21 innobackupex: Connection to database server closed

innobackupex: Backup created in directory '/mnt/2012-07-19_11-52-59'
innobackupex: MySQL binlog position: filename 'shop4-slavedb-bin.000004', position 107
innobackupex: MySQL slave binlog position: master host 'shop4-masterdb-int', filename 'shop4-masterdb.002048', position 420950703
120719 12:55:21 innobackupex: xtrabackup_55 failed! (exit code 1) The backup may not be complete.