On May 19, 10:08pm, Simon Burge wrote:
> When UVM is stable on the pmax, I'll re-run the tests at that time
> with both UVM and non-UVM kernels.  I'll also think about "make build"
> timings in the future too...

  UVM stable?  How about when it even runs?  [I can boot it, but as soon
as it runs out of free memory and the page daemon starts to run, it hangs.
The page daemon seems to hang trying to do I/O.]

> I loaded a copy of /usr/src/sys onto a local disk on the same machine,
> and re-run the tests (sans the -j 10 compile).  In all cases, the make
> of the kernel was quicker, with the best times split between -j 2 and
> -j 3.  The average saving by going to local disk was in the order of 30
> to 40 seconds, or about 2% (if the mental math is correct).

  I'm not suprised that running more than 3 simultaneous jobs doesn't
gain you anything.  I think the only gain you can get would be from doing
CPU processing on one job while others are waiting for disk I/O.  Since the
kernel compile is mostly CPU, there isn't much room for gain.

Michael

-- 
Michael L. Hitch			mhitch@montana.edu
Computer Consultant
Information Technology Center
Montana State University	Bozeman, MT	USA