According to David Rysdam: While burning my CPU.
>
> Well, this is very interesting and I didn't know it.
>
> HOWEVER, there's still something amiss. Or at least there was the other
> day. Let me explain:
>
> I've been having on and off problems with my ISP. Things like not being
> able to connect, dropped connections, slow tranfers over supposedly fast
> connections, etc. On Wed it was being particularly slow all of a sudden
> and I thought to myself "What if someone hacked into my server and is
> tranferring files or something?". So as part of my checking around I
> tried to do a "who" on the server--and I got a "memory exhausted"
The only time i have every seen that is when a system does not have an
"active" swap partition, or possably file.
> message. I had an uptime of about 50 days until then and was down to 2
> MB. I don't know what the cache and buffer values were. I messed with
> this a bit and then decided to reboot. No ISP problems since (although
> that could easily be coincidence). Now I'm back down to ~2 MB but "who"
> works correctly.
>
> In any case the "memory exhausted" message needs an explanation.
>
> Ray Olszewski wrote:
> >
> > At 12:06 PM 6/12/99 -0700, David Rysdam wrote [in part]:
> >
> > >No, I'm definitely leaking memory. From 18 MB free to 2 MB free in
> > >about 3 days.
> > >
> > >What's weird is no processes seem to be taking an undue amount of RAM.
> > >I just have high "cached" and "buffered" values (11 and 13
> > >respectively). I'm getting this info from 'cat /proc/meminfo'.
> > >
> > >When I reboot the same processes are running but the free memory shoots
> > >back up.
> >
> > This is normal Linux behavior; it's not a memory leak. It's exactly what
> > Frank was trying to explain to you in his response. I'll try with a bit more
> > detail.
> >
> > When a process finishes running (or releases a resource), the kernel will,
> > if possible, leave that process or resource in memory, in effect betting
> > that if you used it one, you'll want to use it again soon. Such memory
> > (depending on what it's holding) can be classified as "cached" or
> > "buffered". But if a new process needs eome memory, the kernel will reassign
> > some of this memory (using a dump-the-oldest-stuff-first algorithm, I think)
> > to the new process. It's available, just not *quite* free.
> >
> > To see what's going on, run "free" and look at the difference between the
> > "free" entey on the first line and the one below it on the "+/- buffers"
> > line. The difference is the amount that's holding old stuff against future
> > uses but available if needed for something new.
> >
> > When you reboot, of course, free memory seems to "shoot up" because the
> > buffered processes and data have been lost. Now the program or data will
> > have to be read afresh from the hard disk before it is run or accessed, a
> > slower process than using the RAM buffer.
> >
> > BTW, to see how much this approach can improve perfoemance, try accessing a
> > file from something slow like a CD. As an example, if I make 2 copies of the
> > same bootdisk image, running dd separately for each one, the first will take
> > about 3 times as long as the second. The difference is that for the second,
> > the bootdisk image is already buffered in memory.
> >
> > ------------------------------------"Never tell me the odds!"---
> > Ray Olszewski -- Han Solo
> > Palo Alto, CA 94303-3603 [EMAIL PROTECTED]
> > ----------------------------------------------------------------
>
> --
> My public encryption key is available from
> www.az.com/~drysdam/crypt/rysdam.gpg.html
> and of course www.keyserver.net
>
--
Regards Richard.
[EMAIL PROTECTED]
