Help,Ubuntu Crashed

[usualwyy]

Ubuntu Crashed several times for unknow reasons

Condition:
when or after operating(copy or move or backup) Large files

I think it must be kernel crashed, because Ctrl+SysRq+reisub didn't work anymore

Hardware environment:
I5 450M + ATI HD5430(with official driver) + 320G ATA TOSHIBA + HM55 chipset

Software environment:
Ubuntu X86 X64

Waiting for kindly advice

thanks...

[NightwishFan]

Do a small thing for me:

Decribe what you are doing at the time of the crash, and things you noticed. Also upload /var/log/syslog here for us to peruse.

Hopefully we can help!

[tedygram311]

Try booting from the disk. See if you are able to move things there. Then you could wipe your hard drive and attempt to go from there. I would not do that immediately but that is an option.

[jtarin]

I use this for such things.It allows you to watch kernel messages

A nice trick is to pipe dmesg to tail to watch any message that comes to dmesg. To do this, issue the command dmesg | tail -f and the last few lines of dmesg will remain in your terminal. Every time a new entry arrives it will be at the bottom of the “tail.” Keep this window open when doing heavy duty system administration or debugging a system.

[usualwyy]

NightwishFan & tedygram311

Thank you two kindly guys really

I'm a newbie for Ubuntu

since I used Ubuntu last week,I got system crashed many times a day, even during I used live CD bakup

First time the Ubuntu crashed,I was browsing the web。I drew lesson from this,and after the first time crashed,I didn't do anything during file operating at all, but it still crashed,and I found when I operating large files,it happens 100% and never missed

The files I operated is about 1G to 3G
I mounted the / and /home as EXT4

to NightwishFan:
Before the last time it crashed I noticed that the 3rd CPU runs in 100% and others only 5%,and 1 second later,it crashed

to tedygram311:
I'm very sure that my hard disk is healthy and strong,but I'm not sure what about the drivers
I won't wipe my hard disk anymore,for I had wiped it at least 10 times.

I almost lost confidence with my Ubuntu

I hope you can recognize what I wrote in my bad English
Thanks again for help

[usualwyy]

I use this for such things.It allows you to watch kernel messages

you mean I have to keep this terminal and watch my system break down again?

my goodness

It may be the worst idea I've ever heard

system crash almost drive me crazy。

[usualwyy]

the log is in attachment

Please help me

[NightwishFan]

Only parts of the log I saw that may have been an issue were:

Sep 28 06:33:42 bigchan-laptop kernel: imklog 4.2.0, log source = /proc/kmsg started.
Sep 28 06:33:42 bigchan-laptop rsyslogd: [origin software="rsyslogd" swVersion="4.2.0" x-pid="4016" x-info="http://www.rsyslog.com"] (re)start
Sep 28 06:33:42 bigchan-laptop rsyslogd: rsyslogd's groupid changed to 103
Sep 28 06:33:42 bigchan-laptop rsyslogd: rsyslogd's userid changed to 101
Sep 28 06:33:42 bigchan-laptop rsyslogd-2039: Could no open output file '/dev/xconsole' [try http://www.rsyslog.com/e/2039 ]
Sep 28 06:33:42 bigchan-laptop acpid: 38 rules loaded
Sep 28 06:33:42 bigchan-laptop acpid: waiting for events: event logging is off
Sep 28 06:33:42 bigchan-laptop kernel: [  805.489070] type=1505 audit(1285626822.951:18):  operation="profile_replace" pid=4020 name="/usr/sbin/mysqld"
Sep 28 06:33:43 bigchan-laptop init: udev main process (3803) killed by KILL signal
Sep 28 06:33:43 bigchan-laptop init: udev main process ended, respawning
Sep 28 06:33:43 bigchan-laptop init: dbus main process (3869) killed by KILL signal
Sep 28 06:33:43 bigchan-laptop init: dbus main process ended, respawning
Sep 28 06:33:43 bigchan-laptop init: Disconnected from system bus
Sep 28 06:33:43 bigchan-laptop init: dbus main process (4038) terminated with status 1
Sep 28 06:33:43 bigchan-laptop init: dbus main process ended, respawning
Sep 28 06:33:43 bigchan-laptop init: Unable to connect to the system bus: Failed to connect to socket /var/run/dbus/system_bus_socket: Connection refused
Sep 28 06:33:43 bigchan-laptop kernel: [  805.565872] udev: starting version 151
Sep 28 06:33:43 bigchan-laptop /etc/mysql/debian-start[4049]: Upgrading MySQL tables if necessary.
Sep 28 06:33:43 bigchan-laptop kernel: [  806.507339] SysRq : Emergency Sync
Sep 28 06:33:43 bigchan-laptop kernel: [  806.517628] Emergency Sync complete
Sep 28 06:33:44 bigchan-laptop /etc/mysql/debian-start[4052]: /usr/bin/mysql_upgrade: the '--basedir' option is always ignored
Sep 28 06:33:44 bigchan-laptop /etc/mysql/debian-start[4052]: Looking for 'mysql' as: /usr/bin/mysql
Sep 28 06:33:44 bigchan-laptop /etc/mysql/debian-start[4052]: Looking for 'mysqlcheck' as: /usr/bin/mysqlcheck
Sep 28 06:33:44 bigchan-laptop /etc/mysql/debian-start[4052]: This installation of MySQL is already upgraded to 5.1.41, use --force if you still need to run mysql_upgrade
Sep 28 06:33:44 bigchan-laptop /etc/mysql/debian-start[4059]: Checking for insecure root accounts.
Sep 28 06:33:44 bigchan-laptop /etc/mysql/debian-start[4063]: Triggering myisam-recover for all MyISAM tables
Sep 28 06:33:45 bigchan-laptop kernel: [  807.617602] SysRq : Emergency Remount R/O

I cant make heads or tail of it. >_>