1. 05 Aug, 2003 1 commit
    • Leigh B. Stoller's avatar
      The rest of the sync server additions: · 212cc781
      Leigh B. Stoller authored
      * Parser: Added new tb command to set the name of the sync server:
      
      	tb-set-sync-server <node>
      
        This initializes the sync_server slot of the experiment entry to the
        *vname* of the node that should run the sync server for that
        experiment. In other words, the sync server is per-experiment, runs
        on a node in the experiment, and the user gets to chose which node
        it runs on.
      
      * tmcd and client side setup. Added new syncserver command which
        returns the name of the syncserver and whether the requesting node
        is the lucky one to run the daemon:
      
          SYNCSERVER SERVER='nodeG.syncserver.testbed.emulab.net' ISSERVER=1
      
        The name of the syncserver is written to /var/emulab/boot/syncserver
        on the nodes so that clients can easily figure out where the server
        is.
      
        Aside: The ready bits are now ignored (no DB accesses are made) for
        virtual nodes; they are forced to use the new sync server.
      
      * New os/syncd directory containing the daemon and the client. The
        daemon is pretty simple. It waits for TCP (and UDP, although that
        path is not complete yet) connections, and reads in a little
        structure that gives the name of the "barrier" to wait for, and an
        optional count of clients in the group (this would be used by the
        "master" who initializes barriers for clients). The socket is saved
        (no reply is made, so the client is blocked) until the count reaches
        zero. Then all clients are released by writting back to the
        sockets, and the sockets are closed. Obviously, the number of
        clients is limited by the numbed of FDs (open sockets), hence the
        need for a UDP variant, but that will take more work.
      
        The client has a simple command line interface:
      
          usage: emulab-sync [options]
          -n <name>         Optional barrier name; must be less than 64 bytes long
          -d                Turn on debugging
          -s server         Specify a sync server to connect to
          -p portnum        Specify a port number to connect to
          -i count          Initialize named barrier to count waiters
          -u                Use UDP instead of TCP
      
          The client figures out the server by looking for the file created
          above by libsetup (/var/emulab/boot/syncserver). If you do not
          specify a barrier "name", it uses an internal default. Yes, the
          server can handle multiple barriers (differently named of course)
          at once (non-overlapping clients obviously).
      
          Clients can wait before a barrier in "initialized." The count on
          the barrier just goes negative until someone initializes the
          barrier using the -i option, which increments the count by the
          count. Therefore, the master does not have to arrange to get there
          "first." As an example, consider a master and one client:
      
      	nodeA> /usr/local/etc/emulab/emulab-sync -n mybarrier
      	nodeB> /usr/local/etc/emulab/emulab-sync -n mybarrier -i 1
      
          Node A waits until Node B initializes the barrier (gives it a
          count).  The count is the number of *waiters*, not including the
          master. The master is also blocked until all of the waiters have
          checked in.
      
          I have not made an provision for timeouts or crashed clients. Lets
          see how it goes.
      212cc781
  2. 15 Jul, 2003 1 commit
  3. 02 Jul, 2003 1 commit
    • Leigh B. Stoller's avatar
      Hack for dealing with user output from the parser (puts). Since I spit · 10673342
      Leigh B. Stoller authored
      the XML to stdout, user calls to puts confuse the converter, and get
      lost so the user never sees them (before, they would end up in the
      start/preload log). The converter now eats up lines till it sees a
      valid XML header string, printing those lines to stdout so they end up
      in the log like before.
      
      Need to deal with this in a better manner at some point. I did not
      want to write the XML to temporary file. Not sure why, but I thought
      that was the right approach, to keep the user from getting his grubby
      little hands on it. I'm thinking now thats silly, and I'll eventually
      fix things up (since it requires more TCL hacking, and I don't have
      the energy for that).
      10673342
  4. 30 Jun, 2003 1 commit
    • Leigh B. Stoller's avatar
      Make the new parser live on mini. New parser ssh'es over to ops to · 2202fc5a
      Leigh B. Stoller authored
      do the actual parse. The parser now spits out XML instead of DB
      queries, and the wrapper on boss converts that to DB insertions after
      verification. There are some makefile changes as well to install the
      new parser on ops via NFS, since otherwise the parser could
      intolerably out of date on ops!
      2202fc5a
  5. 26 Jun, 2003 1 commit
    • Leigh B. Stoller's avatar
      New script. Convert experiment to a "well formed" XML, and back again. · f7fc7ff3
      Leigh B. Stoller authored
      The conversion from XML to an experiment representation updates the
      DB, although the experiment has to exist, and only certain fields can
      be updated. For the rest of the virtual toplogy, the old toplogy is
      deleted, and the new one installed. Use with caution. This is intended
      to be hooked to the parser, and later to the vis tool.
      f7fc7ff3