SUSE11的/var/log/gdm下的日志:0-greeter.log* 和:0-slave.log*

SUSE11的/var/log/gdm下的日志:0-greeter.log* 和:0-slave.log*是干什么用的，现在把根目录撑满了，怎么把它配置好？
df -m
Filesystem 1M-blocks Used Available Use% Mounted on
/dev/sda2 12092 11847 0 100% /
udev 3930 1 3930 1% /dev
/dev/mapper/vgdb-lvgdb 60476 4935 52470 9% /home
ls -l
-rw-r--r-- 1 gdm gdm 2043987452 2014-09-23 10:00 :0-greeter.log
-rw-r--r-- 1 gdm gdm 2040581191 2014-09-23 10:00 :0-greeter.log.1
-rw-r--r-- 1 gdm gdm 2033501404 2014-09-22 10:00 :0-greeter.log.2
-rw-r--r-- 1 gdm gdm 2026372108 2014-09-21 10:00 :0-greeter.log.3
-rw-r--r-- 1 gdm gdm 2019292321 2014-09-20 10:00 :0-greeter.log.4
-rw-r--r-- 1 root root 16920 2013-12-09 17:20 :0.log
-rw-r--r-- 1 root root 16920 2013-11-11 09:47 :0.log.1
-rw-r--r-- 1 root root 17226 2012-03-31 13:23 :0.log.2
-rw-r--r-- 1 root root 17205 2012-03-31 13:23 :0.log.3
-rw-r--r-- 1 root root 17063 2012-03-05 14:49 :0.log.4
-rw-r--r-- 1 root root 5407456 2014-09-19 10:27 :0-slave.log
-rw-r--r-- 1 root root 0 2014-09-19 10:27 :0-slave.log.1
-rw-r--r-- 1 root root 0 2014-09-19 10:27 :0-slave.log.2
-rw-r--r-- 1 root root 0 2014-09-19 10:27 :0-slave.log.3
-rw-r--r-- 1 root root 289 2012-03-05 14:24 :0-slave.log.4