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to accept new solutions, so that we don't give violtions any special
treatment.

This can greatly reduce 'thrasing' at low scores, allowing assign to
converge on a solution much faster. For example, in the 1000-node
topology used for the virtualization paper, assign's runtime dropped
from nearly two hours to just over half an hour, with no degredation
in scores found.

You can get the old accept behavior by enabling the
SPECIAL_VIOLATION_TREATMENT #define, which is on right now (hence, we
are not using this change yet.)

Here are the pertinent comments from the code:

#ifdef SPECIAL_VIOLATION_TREATMENT
         /*
          * In this ifdef, we always accept new solutions that have fewer
          * violations than the old solution, and when we're trying to
          * determine whether or not to accept a new solution with a higher
          * score, we don't take violations into the account.
          *
          * The problem with this shows up at low temperatures. What can often
          * happen is that we accept a solution with worse violations but a
          * better (or similar) score. Then, if we were to try, say the first
          * solution (or a score-equivalent one) again, we'd accept it again.
          *
          * What this leads to is 'thrashing', where we have a whole lot of
          * variation of scores over time, but are not making any real
          * progress. This prevents the cooling schedule from converging for
          * much, much longer than it should really take.
          */
#else // no SPECIAL_VIOLATION_TREATMENT
         /*
          * In this branch of the ifdef, we give violations no special
          * treatment when it comes to accepting new solution - we just add
          * them into the score. This makes assign behave in a more 'classic'
          * simulated annealing manner.
          *
          * One consequence, though, is that we have to be more careful with
          * scores. We do not want to be able to get into a situation where
          * adding a violation results in a _lower_ score than a solution with
          * fewer violations.
          */

fix up standalone makefiles
have imagezip -v spit out the FSes it supports

parameter the virtual node it is being called for, and considers only
bandwidths that can be supported by physical nodes that virtual node
can be mapped to.

This fixes some cases where we were mistakenly setting interfaces
on slow links to 10Mbps, which does not work reliably.

Not surpisingly, tracking down problems with vtypes was half the
trouble with making this change.

splitting the existing code between a frontend script that parses arguments
and does taint checking, and a backend library where all the work is done
(including permission checks). The interface to the libraries is simple
right now (didn't want to spend a lot of time on designing interface
without knowing if the approach would work long term).

	use libreboot;
	use libosload;

        nodereboot(\%reboot_args, \%reboot_results);
        osload(\%reload_args, \%reload_results);

Arguments are passed to the libraries in the form of a hash. For example,
in os_setup:

	$reload_args{'debug'}     = $dbg;
	$reload_args{'asyncmode'} = 1;
	$reload_args{'imageid'}   = $imageid;
	$reload_args{'nodelist'}  = [ @nodelist ];

Results are passed back both as a return code (-1 means total failure right
away, while a positive argument indicates the number of nodes that failed),
and in the results hash which gives the status for each individual node. At
the moment it is just success or failure (0 or 1), but in the future might
be something more meaningful.

os_setup can now find out about individual failures, both in reboot and
reload, and alter how it operates afterwards. The main thing is to not wait
for nodes that fail to reboot/reload, and to terminate with no retry when
this happens, since at the moment it indicates an unusual failure, and it
is better to terminate early. In the past an os_load failure would result
in a tbswap retry, and another failure (multiple times). I have already
tested this by trying to load images that have no file on disk; it is nice
to see those failures caught early and the experiment failure to happen
much quicker!

A note about "asyncmode" above. In order to promote parallelism in
os_setup, asyncmode tells the library to fork off a child and return
immediately. Later, os_setup can block and wait for status by calling
back into the library:

	my $foo = nodereboot(\%reboot_args, \%reboot_results);
	nodereboot_wait($foo);

If you are wondering how the child reports individual node status back to
the parent (so it can fill in the results hash), Perl really is a kitchen
sink. I create a pipe with Perl's pipe function and then fork a child to so
the work; the child writes the results to the pipe (status for each node),
and the parent reads that back later when nodereboot_wait() is called,
moving the results into the %reboot_results array. The parent meanwhile can
go on and in the case of os_setup, make more calls to reboot/reload other
nodes, later calling the wait() routines once all have been initiated.
Also worth noting that in order to make the libraries "reentrant" I had to
do some cleaning up and reorganizing of the code. Nothing too major though,
just removal of lots of global variables. I also did some mild unrelated
cleanup of code that had been run over once too many times with a tank.

So how did this work out. Well, for os_setup/os_load it works rather
nicely!

node_reboot is another story. I probably should have left it alone, but
since I had already climbed the curve on osload, I decided to go ahead and
do reboot. The problem is that node_reboot needs to run as root (its a
setuid script), which means it can only be used as a library from something
that is already setuid. os_setup and os_load runs as the user. However,
having a consistent library interface and the ability to cleanly figure out
which individual nodes failed, is a very nice thing.

So I came up with a suitable approach that is hidden in the library. When the
library is entered without proper privs, it silently execs an instance of
node_reboot (the setuid script), and then uses the same trick mentioned
above to read back individual node status. I create the pipe in the parent
before the exec, and set the no-close-on-exec flag. I pass the fileno along
in an environment variable, and the library uses that to the write the
results to, just like above. The result is that os_setup sees the same
interface for both os_load and node_reboot, without having to worry that
one or the other needs to be run setuid.

the tmcd stuff...

"client-install"

comment that LANs don't have queues.

e.g. 50s instead of 50 slots. Expanded the abbreviation coz one of the
users was confused and guessed 50s to be 50 seconds * bandwidth.

operations for plabrenewd.

not n.node_id.

* Added 'leaseend' column to plab_slices table.

* implemented PLC slice renewal
* restructured daemon code/startup
  - removed getfree daemon (replaced by plabdiscover; run from cron)
  - moved generic daemonizing code into libtestbed (class)
  - created plabrenewd - small script that utilizes daemonizing class
  - removed plabdaemon file.
  - updated bossnode startup scripts
* changed slice prefix - PLC denies permission w/ anything other than "utah"
* Minor semantic changes to module API to be more consistent with other parts.
* Some bug fixes.

it out of a file in /usr/testbed/etc .

We put it in a seperate file from the rest of the certificate, because
we need the fingerprint to be publically-readable.

* removed unused and not generally useful ping checking
* reorganized node discovery and added node info updating
  - e.g., update IP, SITE, or HOSTNAME when they have changed
  - no longer part of the backend module as this is independent of
    which backend is used; may modularize it due to plab's new "trumpet"
    service, which is basically its node DB available via a decentralized
    transport/API.
* introduced new method of getting node info - use plab sites.xml file
* various other cleanups.

putting type information into the database by hand.

instead of only 10 characters.

planning to change the size of node_ids.

given OSID, and include this view on the image and osinfo pages.

since some people really do have very short names.

ones. Provide defaults for many fields, when creating a new type.

Re-order a few fields to make a little more sense.

Add a javascript function to build a value for control_iface based on
what the user puts into control_net.