Severe instabilities and system lockups

Al Plant noc at
Fri Mar 12 03:10:05 UTC 2010

David Jackson wrote:
> David Jackson wrote:
>> I am still having severe problems with severe system instabilities 
>> with FreeBSD and have had these problrms in 7.1 and 8.0. The system 
>> randomly locks up, it appears applications lock up when they access 
>> the USb disk. Also, when accessing the USB disk, the entire system 
>> lockup often for minutes. Performance with accessing USB disks is 
>> horrendous,. it took 7 hours to copy a directory that was 200 MB. Any 
>> program that accesses the USB disk tend to freeze for minutes, and 
>> often the entire system becomes unresponsive for minutes. Overall 
>> FreeBSD here is characterized by severe instabilities, ive had better 
>> performance from Windows 98 systems. The fact that the entire system 
>> freezes up, this should not happen, a well designed system will not 
>> lock up the entire OS when accessing disk.
>> Are there any diagnostic tools uch as getting a log of tranmissions on 
>> USB and probe it, ,or finmd out what code it is lockilng up on ?Has 
>> anyone else seen these problems with USB disks?
> Thank you for the reply to my concerns. I have been reading through them 
> carefully.
> I seem to have also discovered that the lockup problems are not entirely 
> due to USB issues. Many of them were being caused by an apparent problem 
> with the swap system. I have two swaps, a file backed swap and a 
> partition swap on the same disk. Apparently when having two swaps on the 
> disk there are severe performance problems. FreeBSD needs to fix 
> whatever is causing this thrashing problem. So far the lockups have seem 
> to become much less severe since i have disabled the file based swap 
> file. I may disable the partition swap but i do not know if it is 
> possible to have the system boot with a file based swap only. Perhaps i 
> can disable the partition swap after it boots.
> I am trying to copy a directory on the USB drive however and it does 
> seem to be rather slow still. It started at 5:45 and is still going. I 
> will see how long it takes.
> Again thanks for the help with these issues
> _______________________________________________

I dont think its a good idea to have two swaps on any HD.
If you used the default setup under sysinstall for FreeBSD it gives how 
the setup should look.

Is the USB a current 2.0? I cant ever recall having the problems you are 
describing on a FreeBSD box ever.

Maybe you have funky hardware configuration.

~Al Plant - Honolulu, Hawaii -  Phone:  808-284-2740
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