PVMOnPatas < Main

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---+ Using PVM on the patas cluster

---++ Setup

While the version of Condor we have installed does not currently support scheduling PVM applications, running PVM in parallel with Condor works fine. It does, however, require a small amount of setup on your account so PVM can run software on the compute nodes without asking for your password.

   1 Log into patas.ling.washington.edu and run =ssh-keygen= to create an SSH key for yourself. Accept the default file location, and use a blank passphrase.
   1 Add the new key into your authorized_keys file, and restrict the file permissions: 
      1 =cat ~/.ssh/id_rsa.pub &gt;&gt;~/.ssh/authorized_keys=
      1 =chmod 600 ~/.ssh/authorized_keys=
   1 Add the host keys for the nodes to your known_hosts file: =cat /opt/etc/ssh-host-keys &gt;&gt;~/.ssh/known_hosts=

---++ Testing

Try running pvm and adding a few of the compute nodes as hosts. You should get something like this:
<verbatim>
user@patas:~$ pvm
pvm> add patas-n1
add patas-n1
1 successful
                    HOST     DTID
                 patas-n1    80000
pvm> add patas-n2
add patas-n2
1 successful
                    HOST     DTID
                 patas-n2    c0000
pvm> add patas-n3
add patas-n3
1 successful
                    HOST     DTID
                 patas-n3   100000
</verbatim>

---++ Usage notes
 By default, PVM is set up to use the system's PVM installation, in /usr/share/pvm3. If the program you're running includes its own PVM implementation, you may need to change the settings of the =PVM_ROOT= and =PVM_ARCH= environment variables.

You can always find out what nodes are available by running =condor_status= and looking at the left column. Only the part of the hostname between the @ sign and the first dot is needed by PVM (e.g., "patas-n1").

If you are having trouble adding a node, check that the troublesome nodes don't have pvmd running already. Check the /tmp/ directory on the node for files like .pvm.socket.username, where "username" is your user name. You may have to remove this file to force pvmd to halt on this machine.
---++ Usage with Logon software

 The Logon tree distributes its own version of pvm and pvmd3, which reside in logon/lingo/lkb/bin/linux.x86.64/ (or ...linux.x86.32 if you are running a 32bit machine). As noted above, you will need to set your PVM_ROOT variable to this path. Logon's version of pvm does not seem to work well with short hostnames (eg. patas-n1) and so you should expand these (eg. patas-n1.ling.washington.edu). These expansions may have to take place in your ~/.ssh/known_hosts and ~/.pvm_hosts files.

Start pvmd like this (assumes you have the Logon tree in your home directory):

<literal>~/logon/lingo/lkb/bin/linux.x86.64/pvmd3 ~/.pvm_hosts </literal>

-- Main.goodmami - 13 Apr 2009
Topic revision: r2 - 2009-04-13 - goodmami