Re: Parallel build

[Paul Smith]

On Tue, 2012-02-28 at 17:57 +0400, niXman wrote:
> Hello,
> 
> I built make from CVS. I'am confused that option "-jN" didn't work properly.
> When I set N to count (doesn't matter how much I set) It will build
> using 1 thread.
> If I'm use this option without setting count It'll build with a lot of
> threads (more than 20).
> Why does make work not properly?

You'll have to provide a test case, and explain what happens, otherwise
we can't help.

This makefile, for example, works correctly for me on GNU/Linux (with
-j2 I get two jobs at a time running):

        all: 1.p 2.p 3.p 4.p 5.p 6.p
        .PHONY: all
        %.p: ; @echo start $* && sleep 2 && echo end $*

Using this I can see that the first two run, then a pause, then the next
two, etc.:

        start 1
        start 2
        end 1
        end 2
        start 3
        start 4
        end 3
        end 4
        start 5
        start 6
        end 5
        end 6

-- 
-------------------------------------------------------------------------------
 Paul D. Smith <address@hidden>          Find some GNU make tips at:
 http://www.gnu.org                      http://make.mad-scientist.net
 "Please remain calm...I may be mad, but I am a professional." --Mad Scientist