Makeflow Tutorial

Download and Installation

First log into the UA HPC center head node frost.hpc.arizona.edu by using ssh, Putty, or a similar tool. Once you have a shell, download and install the cctools software in your home directory in one of two ways:

To install a binary package (faster):

To build from source (slower):

wget http://ccl.cse.nd.edu/software/files/cctools-6.0.2-x86_64-redhat6.tar.gz
tar xvzf cctools-6.0.2-x86_64-redhat6.tar.gz
mv cctools-6.0.2-x86_64-redhat6 cctools

git clone https://github.com/cooperative-computing-lab/cctools cctools-src
cd cctools-src
./configure --prefix $HOME/cctools
make
make install
cd $HOME

If you use bash then do this to set your path:

export PATH=$HOME/cctools/bin:$PATH

If you use tcsh instead, then do this:

setenv PATH $HOME/cctools/bin:$PATH

Now double check that you can run the various commands, like this:

makeflow -v
work_queue_worker -v
work_queue_status

Makeflow Example

Let's being by using Makeflow to run a handful of simulation codes. First, make and enter a clean directory to work in:

cd $HOME
mkdir tutorial
cd tutorial

Now, download this program, which performs a highly sophisticated simulation of black holes colliding together:

wget http://ccl.cse.nd.edu/software/tutorials/acic16/simulation.py

Try running it once, just to see what it does:

chmod 755 simulation.py
./simulation.py 5

Now, let's use Makeflow to run several simulations. Create a file called example.makeflow and paste the following text into it:

input.txt:
	LOCAL /bin/echo "Hello Makeflow!" > input.txt

output.1: simulation.py input.txt
	./simulation.py 1 < input.txt > output.1

output.2: simulation.py input.txt
	./simulation.py 2 < input.txt > output.2

output.3: simulation.py input.txt
	./simulation.py 3 < input.txt > output.3

output.4: simulation.py input.txt
	./simulation.py 4 < input.txt > output.4

To run it on your local machine, one job at a time:

makeflow example.makeflow -j 1

Note that if you run it a second time, nothing will happen, because all of the files are built:

makeflow example.makeflow
makeflow: nothing left to do

Use the -c option to clean everything up before trying it again:

makeflow -c example.makeflow

Arizona HPC uses the PBS batch system, so to run your jobs through PBS, do this: (Note that the -B option passes a bunch of details required by UA HPC.)

makeflow -T pbs -B "-W group_list=ericlyons -q windfall -ljobtype=serial -lselect=1:ncpus=1:mem=1gb -lpack:shared" example.makeflow

If you are working at another site that uses Condor or Torque or SGE, then you would invoke makeflow like this instead:

makeflow -T condor example.makeflow
makeflow -T torque example.makeflow
makeflow -T sge example.makeflow

Running Makeflow with Work Queue

You will notice that a workflow can run very slowly if you submit each job individually, because it typically takes 30 seconds or longer to start each batch job running. To get around this limitation, we provide the Work Queue system. This allows Makeflow to function as a master process that quickly dispatches work to remote worker processes.

makeflow -c example.makeflow
makeflow -T wq example.makeflow -p 0
listening for workers on port XXXX.
...

Now open up another shell and run a single worker process:

work_queue_worker frost.hpc.arizona.edu XXXX

Go back to your first shell and observe that the makeflow has finished. Of course, remembering port numbers all the time gets old fast, so try the same thing again, but using a project name:

makeflow -c example.makeflow
makeflow -T wq example.makeflow -N MYPROJECT
listening for workers on port XXXX
...

Now open up another shell and run your worker with a project name:

work_queue_worker -N MYPROJECT

Running Workers in PBS

Note: This step doesn't work at UA HPC, due to some local firewall limitations, but the same technique works at other sites.

Of course, we don't really want to run workers on the head node, so let's instead use pbs_submit_workers to set up five workers in PBS for us:

pbs_submit_workers -N MYPROJECT 5
Creating worker submit scripts in dthain-workers...
2065026.i136
2065027.i136
2065028.i136
2065029.i136
2065030.i136

Use the qstat command to observe that they are submitted to PBS:

qstat
2065027.i136               worker.sh        dthain                 0 R batch
2065028.i136               worker.sh        dthain                 0 R batch
2065029.i136               worker.sh        dthain                 0 R batch 
2065030.i136               worker.sh        dthain                 0 R batch

Now, restart your Makeflow and it will use the workers already running in PBS:

makeflow -c example.makeflow
makeflow -T wq example.makeflow -N MYPROJECT
listening for workers on port XXXX.
...

You can leave the workers running there, if you want to start another Makeflow. They will remain until they have been idle for fifteen minutes, then will stop automatically.

If you add the -d all option to Makeflow, it will display debugging information that shows where each task was sent, when it was returned, and so forth:

makeflow -c example.makeflow
makeflow -T wq example.makeflow -N MYPROJECT -d all
listening for workers on port XXXX.

Homework

Now you have everything needed to do the Homework Assignment.