[NBLUG/talk] memory leak question

[Sameer Verma]

E Frank Ball III wrote:
> On Sun, Mar 16, 2008 at 10:43:01AM -0700, Kyle Rankin wrote:
>  > On Sun, Mar 16, 2008 at 10:19:37AM -0700, Sean wrote:
>  > > I suspect I might be having a memory leak problem, but I don't know
>  > > how to check for it properly.
>  > 
>  > 
>  > greenfly at minimus:~$ free
>  >              total       used       free     shared    buffers     cached
>  > Mem:       1026288    1002648      23640          0       5820     447888
>  > -/+ buffers/cache:     548940     477348
>  > Swap:      1052216      34776    1017440
>  > 
>  > It might look like I've used almost all of my 1Gb of RAM on this system
>  > according to the used column, but look at the far right to the cached
>  > column. It shows that I have 447Mb cached. When you open files, if Linux
>  > has spare RAM, it actually caches some of those open files into memory. The
>  > idea is, if you have RAM to spare, the next time you open the file, it will
>  > open much faster since it's already in RAM.
>  > 
>  > Because of this, at first glance basically all Linux systems will appear to
>  > be consuming all available RAM after the system has been up for awhile. The
>  > best way to check the actual used RAM is to skip down to to the -/+
>  > buffers/cache. If you look there you'll see that I have 548940Kb actually
>  > in use, and 477348Kb free.
>
> I use a gizmo called xosview (it's in Debian).  It shows memory usage
> broken down into user/buffer/cache on a bar graph.
>
> And Firefox will suck up lots of memory over time.  I need to restart it
> every few days.
>
>   
Just a note on FF memory problems. There's large mem footprint and then 
there's mem leak, which leads to a growing mem footprint. A good bit of 
memory problems with FF will come from third-party extensions for FF. 
There is close to zero quality control with extensions (other than users 
complaining) so even if FF3 looks good, any bad extension can result in 
a bad experience.

Sameer

-- 
Dr. Sameer Verma, Ph.D.
Associate Professor of Information Systems
San Francisco State University
San Francisco CA 94132 USA
http://verma.sfsu.edu/
http://opensource.sfsu.edu/