Re: More slowness with 7.1

[Ken Siersma <Ken Siersma ekkinc com>]

So now I'm running 2.4.10 with Ivan's patch to mmap.c, and at first it ran much
better than before.  There was no hesitation,  there was a small amount of swap
usage - which I don't understand.  Free told me 311088 of swap was used at the
height of my large process.  Only when I had two CPU consuming processes running
did I see any hesitation at all, and it was only slight.

But then unexpectedly the machine crashed.  I took a look at /var/log/messages,
and there are many of the following:

    Oct  1 10:18:16 hurricane kernel: X(657): unaligned trap at 0000000120a173f4:
0000000120b6e5d6 2c 28
    Oct  1 10:18:16 hurricane kernel: X(657): unaligned trap at 0000000120a173f4:
0000000120b6e5da 2c 28
    Oct  1 10:18:16 hurricane kernel: X(657): unaligned trap at 0000000120a173f4:
0000000120b6e5de 2c 28

I'm expecting it to crash any second now, so I'm going to send this email
Ken

"Christopher C. Chimelis" wrote:

> On Fri, 28 Sep 2001, Ken Siersma wrote:
>
> > No, this process is a FORTRAN number crunching program that is not
> > multithreaded.  The process does a good job of dominating one of the
> > processors, and the other one is free to do everything else, but it just
> > does so very slowly.  If you don't think it is the kernel, could it be one
> > of the daemons?  There are a lot of new daemons in 7.1 compared to 6.2 that
> > I don't fully understand yet.  Besides, when I was running RH 6.2, I had
> > 2.4.2 running successfully on the machine.  So I don't think it is something
> > inherent in all 2.4 kernels.
>
> Hmmm...yeah, could be the VM thrashing the system to death.  I know you
> shouldn't be, but are you hitting swap at all?  Doubtful, but I'm curious
> :-P  Also, I'm not sure if they're still around, but there are some
> patches for more efficient use of >1GB RAM.  I think they're in Andrea's
> dir on ftp.kernel.org.
>
> C

--
Ken Siersma, Software Engineer
EKK, Inc.
100 North Pond Drive Suite A
Walled Lake, Michigan, 48390  USA
phone: (248) 624-9957
fax: (248) 624-7158
http://www.ekkinc.com