Re: GNU make multiple jobs option

[Andrew Johnson <anj@aps.anl.gov>]

Janet Anderson wrote:
> Yesterday I committed changes to the EPICS base  R3.14 branch and the 
> main trunk  to allow the GNU make "-j jobs" option to work when building 
> EPICS base.  I also made a change in the makeBaseApp.pl templates to 
> allow the -j option when building new ioc applications . There is a note 
> about the -j change in the R3.14 branch  release notes.

Note that Janet's parallel build rules that support the -j option 
require the use of $(eval ...) which was introduced in GNU Make version 
3.81.  Serial compilation still works on older versions of Make as 
before, but if you give a -j option the build will fail since many of 
the dependencies won't have been set.

On our 8-core Linux box the performance gain is obvious; building Base 
for Linux and one RTEMS target came down from 6 minutes to 2 minutes in 
my test.

- Andrew
--
When a distinguished but elderly scientist states that something is
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