Re: Kernel math prob? or other problem? (fwd)

Mathew G. Monroe (mmex@shadowland.pc.cc.cmu.edu)
Wed, 28 Jun 1995 04:04:46 -0400 (EDT)


>
> I only slightly suspect this to be a kernel related issue, but I think
> it is likely enough to post to the kernel list. At least you can tell
> me if it is relevant.
>
> I run a web server that generates a lot of traffic, and I use the
> 'wwwstat' program, which is a perl script that parses the ncsa httpd
> logfiles to summarize.
>
> Every time I attempt to run the program against my data, it gets about
> 1/3 of the way through, and aborts with a "Floating Point Exception".
>
> Now, is that fp exception at the system level? Or is it Perl itself
> telling me?
>
> This is running on a 486dx4/100, 16 MB Ram+32M swap, and we've gotten
> the same results with various kernels 1.2.x (up to .8) I'm building
> 1.2.11 right now to try it.
>
> For the purpose of sanity checking, I ran the same data, same script,
> same perl version on a sun sparc 5, 16 MB Ram+32M swap, and the script
> completed successfully.
>
>
> Thanks for any help you can give me.
>
>
> ------------------------+----------------------------------------------
> James L. McGill | Professional Internet Consulting [PICnet]
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>

This is actually a program error, at least it appears to be. SunOS provides
the matherr fucntion, Linux does not. The matherr function catchs floating
point exceptions. From what I can tell it is not part of POSIX, so Linux
doesn't support it. I would guess you are getting floating point exceptions
on both platforms, just the SunOS version hides it. Either the program or
perl installed a copy of matherr, so you dont get to find out about it. Of
course I could always be wrong.

Matt