On Monday 08 December 2008 18:41:25 Wolfgang Denk wrote:
Add logic to the MAKEALL script to determine the number of CPU cores on the system, and run a parallel build if there is more than one. Usually this significantrly accelerates builds.
Allow to manually adjust the number of parallel make jobs by using the "BUILD_NCPUS" environment variable.
Signed-off-by: Wolfgang Denk wd@denx.de
MAKEALL | 11 ++++++++++- 1 files changed, 10 insertions(+), 1 deletions(-)
diff --git a/MAKEALL b/MAKEALL index dbed268..a16549c 100755 --- a/MAKEALL +++ b/MAKEALL @@ -1,6 +1,15 @@ #!/bin/sh
-: ${JOBS:=} +# Determine number of CPU cores if no default was set +: ${BUILD_NCPUS:="`getconf _NPROCESSORS_ONLN`"}
+if [ "$BUILD_NCPUS" -gt 1 ]
no point in quoting here ... if it isnt numeric, then -gt will fail, and all numeric values lack whitespace ...
+then
- JOBS=-j`expr "$BUILD_NCPUS" + 1`
+else
- JOBS=""
+fi
i generally see the heuristic (cpus * 2) rather than (cpus + 1) ... benchmarks tend to favor that as well ...
but this is certainly better than previous behavior: always use -j1 ... -mike