Mailinglist Archive: opensuse (3397 mails)

[John Sowden <jsowden@xxxxxxxxxxxxxxxxxx>]

On Sunday 24 April 2005 15:31, Randall R Schulz wrote:
> Carlos, John,
>
> On Sunday 24 April 2005 05:36, Carlos E. R. wrote:
> > The Saturday 2005-04-23 at 20:35 -0700, John Sowden wrote:
> > > I am running a 48MB 133Mhz machine with Suse 8.0
> > > It has worked fine on the net until today.  The spped slowed down
> > > often to less than 100 bytes per second, and the hard drive
> > > thrashed for hours.
> > >
> > > Questions:
> > > Should the swap partition be empty upon cold boot?  If so what is
> > > the command to test it to see how full it is, and to empty it, and
> > > in which boot file should it go?
> >
> > There is no such thing, and no need either. Your problem must be
> > something else.
> >
> > > It took me 8 hours to look at about 30 web pages of a ecommerce
> > > site.  I never was able to make my purchases.  Sometimes, it would
> > > take 15 minutes to bring a page up.  more ram is an easy answer,
> > > but this is an old machine, and 48MB is overkill for other work.
> > > what has changed?
> >
> > My guess is that those pages are using java, and java needs a lot of
> > memory. As you don't have it, it swaps a lot. I had the same problem
> > three years back, and had to upgrade the computer, no other way:
> > memory for old computers is prohibitive.
>
> As a blanket statement, "Java [software] needs a lot of memory" is not
> particularly accurate.
>
> As a Java programmer who has worked on some programs that _do_ use a lot
> of memory (by their nature, whether implemented in Java or something
> conventionally thought of as more parsimonious), I've noticed that when
> the program's demand for memory approaches the limit imposed by the
> Java Virtual Machine at the time it was launched, performance degrades
> very badly. This happens because the JVM must perform more and more
> garbage collection. This will not lead to swapping unless the Java heap
> limit is set large enough to cause the OS in which it's running to
> page. The default JVM heap limit won't do that on any system that's not
> already on the brink of thrashing.
>
> However, I now look back and see that John says "48 MB is overkill."
> From that perspective, Carlos is right. You'll have trouble running
> non-trivial Java code with so little RAM. In fact, I don't see how
> you're running a GUI environment of any sort in so little RAM.
>
> Generally speaking, the solution to such a problem with Java software is
> to increase the JVM maximum heap size by specifying the -Xmx<size>
> option, but I don't know how to do that for applets running within a
> browser.
>
> John, which browser and which JVM release are you using?
>
> >        Carlos Robinson
>
> Randall Schulz

First, thanks for all the feedback. 

I am running the Konq that came with Suse 8.0.
I do not know which JVM I am running, but I did not install it,
so I assume it is the one that came with Suse 8.0.
If you tell me how, I will check that (and learn how at the same time!)
re: 48MB is overkill _for other work_, I was referring to MS-DOS 7.0 that I 
use on the other computers in our office, and this one (boots DOS/Linux), as 
well as my 128MB 1.3GHz Suse 8.2 machine (also boots DOS/Linux).  I run our 
mission critical and business stuff on DOS, although I am in the process of 
re-writing all spreadsheets to open office.
re: this thrashing issue, it seems to happen after I have been on the net for 
several hours, not when the machine is first turne on.  Also I went back to 
the electronics supplier site (mpjs.com) after shutting off the machine.  It 
degraded after about 15 minutes.

---
John Sowden
American Sentry Systems. Inc.
1221 Andersen Drive
San Rafael, CA  94901

U.L. Listed Central Station Alarm Service
Serving the San Francisco Bay Area Since 1967

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