Metis MapReduce
---------------

Metis is tested on 64-bit Linux but also runs on 32-bit Linux.

Some example MapReduce applications are included.  For a list:
  $ ls app/*.c
  foo.c wc.c wr.c ...

To build and run the example foo.c do:
  $ make obj/foo
  $ obj/foo [args]

If you want to run a MapReduce application that uses Streamflow you
will need to set the environment variable LD_LIBRARY_PATH so ld.so
can find libstreamflow.so:

  $ make obj/foo.sf
  $ LD_LIBRARY_PATH=$LD_LIBRARY_PATH:obj/lib/ obj/foo.sf

The test/test.pl script runs all the tests mentioned in Metis technical
report. To run the test, you need to download the data files at
pdos.csail.mit.edu/metis/data.tar.gz into the top-level directory of
Metis source tree, unpack it, and execute $(Metis_TOP)/data/data-gen.sh
to generate the inputs for all applications.

Metis can take advantage of Linux super pages to reduce the contentions
on page faults. The is achieved by modifying Streamflow to allocate
memory from hugetlbfs. See GNUmakefile for more details about how to
enable hugetlb.

As described in Metis technical report, Metis can be configured to use
different data structures to organize the intermediate key/value pairs,
although we beleive the default configuration is generally efficient
across all workloads. See lib/mr-conf.h for more details.