Re: bug (trouble?) report on high mem support

Alan Cox
2002-03-15T20:15:01Z

> Here is a top output. We have 16Gb of ram.
> I have also tried a 2.4.9-31 enterprise=20
> kernel rpm from RedHat with the same=20
> results.

Ok that would make sense. Next question is do you have an I/O controller
that can use all the 64bit address space on the PCI bus ?

What is happening is that you are using a lot of CPU copying buffers down
into lower memory to transfer to/from disk - as well probably as that
causing a lot of competition for low memory. If your I/O controller can hit
the full 64bit space there are some rather nice test patches that should
completely obliterate the problem.

Alan