Linux System Freeze

eaux-yeah said

Hey Philip.
Never messed around with Oracle Linux, basically a RHEL copy?

It sounds like a 'limits' or 'shared memory' problem. May need to manually set the hard and soft limits and/or tweak the SHM* settings?

I would consider 1Gb memory to be bare minimum for just about any operating system these days, real cheap, too. Increasing swap to compensate for lack of memory is a not the best approach. I would at least create the swap partition on a separate (and fast) drive. Once again, memory very cheap.

Using 'top' is just about the equivalent of your car's 'idiot lights', maybe a bit more informative, though. :hihi:
I would recommend using 'vmstat', 'iostat', or better yet ........ DSTAT!

Do you see any strange information in the 'dmesg' output?
LSOF can help you find out if incorrect libraries or plug-ins, etc. are being used.

Hope that helps.

Click to expand...

Yeah, I think RH and Oracle have a partnership and Oracle tweaks the RH distro to customize for running Oracle.

I've got shared mem settings, limits, kernel parameters all set per the Oracle install guides. In fact, Oracle will not even install unless these parameters are set appropriately.

I'll check out those utilities you mention to see if I can discern anything.

Meanwhile, I've shut the Oracle app server down on machine (1) as an experiment to see if the system stays up. At this point, I can't be convinced it's even Oracle-related without more data points.

The other thing I failed to mention is that both machines are on wireless LAN. I had some headaches getting that going using ndiswrapper and wpasupplicant. I'm new to the wireless thing (just set up my wireless LAN at the same time that I built these 2 machines) and have been disappointed to see that these machines sometimes lose connectivity. I scripted cron jobs for both systems to poll the network to see if it's still up. If not, the script restarts the network. I manage my entire LAN via wireless laptop and have also noticed that the servers are occassionaly sluggish/slow to respond. I have no idea of the wireless woes are contributing to the freeze. Probably not.

I also hacked my router and installed the DD-WRT firmware which allows increasing the radio transmission in an effort to address this situation. I might need to revisit that. ??

Much like the 1 gig of RAM, I realize that wireless isn't ideal for running a production system, but it's not. It's serving just me. I'm just a hacker that likes to see what I can build/tweak around the house. :)

Thanks for all the info!