[ale] BogoMips uselsess?

[Clay Lawrence]

I've found make -j n where n=RAM/8 works fairly well and keeps this from
happening. Where RAM=32 n is 4 but for people like me where RAM=512  is
64 :-)

Clay
Michael Hirsch wrote:
> 
> UnderGrid Founder writes:
> > Chris Ricker decided to waste my bandwidth saying:
> > >
> > > make -j # bzImage
> > >
> >       Better yet... if you got the RAM to spare just run it with the command
> > 'make -j bzImage' and let it run as many processes and use as much RAM as it
> > needs
> 
> ACK!  Not a good idea unless you really know what you are doing.
> 
> > ... on a nice dual PII-400 with plenty of RAM (512MB) I've seen it run
> > up to 513 process and the load to 88 and still have over 100MB of the RAM
> > left untouched and never touch swap space...
> 
> Yes, you prefaced it with "if you've got lots of RAM", but that is a
> weak warning.  If you don't have the RAM this will slow your machine
> to a crawl.  For instance, if you have 96 Meg of RAM you might think
> you have "lots", but in the example provided you would have become I/O
> bound.
> 
> I speak from experience.  I tried to compile something (the GIMP?)
> with -j and only 32 Meg of RAM but I have just added a whole bunch of
> swap so I had something like 160 MB of Swap.  When the number of
> processes hit 65 I finally maned to move the mouse into a another
> window and kill the parent process.
> 
> --Michael