On Monday, December 20, 2010 08:00:36 pm Joseph Apuzzo wrote:
> The one thing I can think of is when a disk runs out of room it shows down
> because it becomes harder and harder to find a place to put new data. How
> full is your disk? There is iozone for benchmarking Disk IO but without the
> original IO speeds it would be almost impossible to tell if there is an
> issue.

It's still possible to see if I/O is reasonable with something like 'iotop' as 
long as you're running a kernel that has I/O accounting enabled (I don't, but 
the default Ubuntu kernel probably does).

> I would use "system monitor" and add the Disk IO graph and see if
> that is the issue or is it memory or CPU. Lastly I would look at "top" in a
> terminal to see what is consuming resource. I have seen background indexing
> eat up 20% of the CPU and almost 40% of IO.

You mean that stupid updatedb process for the 'locate' command?  Or do you 
mean the new absolutely asinine "Desktop Serach" indexing such as 
nepomuk/strigi?  I've found that the "Desktop Serach" indexing is a *huge* 
performance hog, and has several issues associated with it concerning 
'inotify' watches.  In particular what I saw was that simply *selecting* a 
list of, say, 100 files in a file browser would take more than 30 seconds to 
accomplish, and hanging the GUI until it finished, until I finally got sick of 
it and turned the "Desktop Search" features completely off.

And after I did that I found that the database for the Desktop Search features 
was over 1 GiB in size, which has to be manually cleaned/removed.  :-/  It's 
no wonder I was having performance problems there.  So yeah, with newer 
systems there are some things that can run *much* slower, unfortunately.  And 
yes, this is something that caused gradual speed degradation on my system, 
just as Kris describes.  Eventually I traced it down to 'nepomuk' by running 
'top' during performance lags.

> Good practice is to empty the apt cache of old deb updates with "sudo
> apt-get auto-clean" and or "sudo apt-get clean"

Cleaning the apt-get cache of packages is a good idea and can gain back a lot 
of free space after major upgrades or on systems that get lots of updates over 
time... but other than eating space the apt-get cache doesn't cause consistent 
performance problems like are being described.

> There are many hints and tricks around on cleaning up Ubuntu/Debian
> systems.

Anything you'd recommend beyond the "sudo apt-get clean" after using the 
package manager?  I can't think of anything else other than that.  [And 
turning OFF the "Desktop Search" performance hogging features.]

  -- Chris

--

Chris Knadle
[email protected]

> On Mon, Dec 20, 2010 at 6:50 PM, Kristoffer Walker
> 
> <[email protected]>wrote:
> > I upgraded to Ubuntu 10.10 (desktop) a couple of months ago and have
> > seen my performance drop ever since. It is now getting to the point
> > that it is becoming unacceptable. From all my observations it seems
> > like disk IO is creating the bottleneck.
> > 
> > I only thing I did majorly different was to install the entire distro
> > on one disk partition (I've broken it up over 4 partitions in the
> > past). My swap partition is the same size it's always been.
> > 
> > Any ideas how I might isolate the problem, or at least be able to get
> > some actual data that would indicate that disk IO is indeed my issue?
> > 
> > - Kris Walker
_______________________________________________
Mid-Hudson Valley Linux Users Group                  http://mhvlug.org
http://mhvlug.org/cgi-bin/mailman/listinfo/mhvlug

Upcoming Meetings (6pm - 8pm)                         MHVLS Auditorium
  Jan 5 - Building a Community Site with Drupal
  Feb 2 - Zimbra
  Mar 2 - MHVLUG 8th Anniversary - Show and Tell

Reply via email to