[Hadoop-common-dev] hadoop parameters config files location

Hi,
I want to change the following hadoop parameters before launching TeraSort
program:
io.sort.factor
io.sort.mb
mapreduce.reduce.tasks
io.file.buffer.size
io.sort.record.percent

I tried to change these properties by putting them as property values in
core-site.xml file under conf directory.
However, I am unable to observe the effect of my changes to these
parameters.

Could someone elaborate as to which config files, these parameters need to
be configured like core-site.xml or mapred-site.xml or hdfs-site.xml.

Thanks,
Bikash