F7 now super slow, will it infect Fedora 8?

[Doug Purdy]

Monday 04/02/2008 at 14:05, Phil Meyer wrote:
> Tim wrote:
> > On Sun, 2008-02-03 at 21:57 -0500, Doug Purdy wrote:
> >   
> >> Since before Dec 25 both my FC2 and my F7 computers have been running
> >> super slow. Both machines also have XT and that ran fine in informal
> >> tests this weekend, that is, XT responded well and exhibited no
> >> slowness or crashes. 
> >>     
> >
> > "XT"?

Boy, what a mistake! I should have typed XP.

> > If it weren't two computers, cooling would have been the first thing to
> > spring to mind (it could still be, if you're in a hot environment).
> > Things like fans and heatsinks gunked up with fluff stops them working
> > right, and some systems will slow the CPU down to stop it burning out.

The Fedora 7 computer is now clean and the casing is off. The power
supply exhaust is noticeably cooler. The Fedora Core 2 computer is still
running fine.

> > The other thing that springs to mind with two computers, is whether
> > you've been compromised.  You could check for a rootkit, but this is
> > just a wild stab in the dark.

This sounds tougher to check so I'll do the easy verifications first.

> > Taking minutes to finish booting could also point the finger at name
> > resolution not working, if you have services that need to know their
> > network addresses.

Tim, the FC2 computer is just a normal desktop install and it's not
providing nor using shared directories or databases. There are only 8
computers and a network printer on this home LAN. See below, cpu cycles
and memory appear to be being gobbled up somewhere.

> >   
> 
> Another thing to look at is memory.  On systems with 256MB or less, 
> applications will get totally paged out over night during cron activity.
> 
> When these applications attempt to run the next day, they can take 
> minutes to page back in, depending upon HD speeds and application size.
> 
> Rebooting appears to solve the problem only because there is nothing 
> cached in memory and the system can load new things without having to 
> reorganize physical memory.
> 
> XP will not show the same symptoms on these systems because it does not 
> run the same level of disk heavy cron jobs (logwatch, updatedb, 
> makewhatis, and prelink).
> 
> XP also does not have a very robust paging system and can simply fail 
> applications when physical memory is exceeded.
> 
> All I am suggesting, is that there is a good reason that the Fedora 
> developers have moved the recommended memory requirement to 512MB.  
> Fedora, and many other Linux distros can be made to run in 128MB or even 
> less, but you have to know what you are doing, and limit what you use it 
> for.
> 
> In general, memory helps all UNIX/Linux based systems.  The more memory 
> the better, and 2GB desktop systems are becoming common place.
> 
> Good Luck!

Thanks Phil! Memory does seem to be the problem on the 1.2gig Fedora 7
computer. With System Monitor the only application running, memory usage
climbs continuously at about 10 megs a minute. It's now into the swap
file for 230 megs. CPU usage is about 25% even though System monitor is
only using 2-6%. The 760 meg Fedora Core 2 computer is still acting
normally and reporting memory and CPU usage in agreement with the
processes reported by System Monitor.

How do I investigate what invisible process is using the CPU and memory?

Doug