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code originally tried to do a normal $ns connect between traffic agents
attached to simnodes on the same pnode. The problem that I forgot of course
is that partitioned topology is quite disconnected which means that a
packet is forced to exit the pnode and come back to it (in many cases).
In other words, a direct intra pnode path does not exist. The fix is
to just use the IP address based routes always. A similar problem
is encountered in pdns as well. However, since IP address based routing
is not used, there is no simple fix unless I work on it!

The 416 node topology testbed/nse416 is working alright. It mapped to
20 pnodes and as soon as a whole bunch of traffic started up, 7 pnodes
couldn't track real-time and caused a modify. Expt modify happened 3
times but eventually max_retries in my re-swapping code was reached. Need
more measuring, tuning as well as eventrate based re-swapping.

a simple problem in the duplex-link instproc which caused the code for
simnode creation to go to one pnode while an rlink from this simnode
was mapped to another pnode.

Also added $ns rtproto Manual for generated tcl code since IP address
based routes are being added.

I'm trying to get a handle on what to write for the paper...

(or more than one simhost) is unable to keep up with real-time. It includes
changes to assign_wrapper to handle swap modify for simnodes, the simple
algorithm in nseswap that bumps up the nodeweight of simnodes being hosted
on a simhost that reports "can't keep up with real-time" (aka nse violation),
ptopgen and sim.tcl to prefer nodes that already have the FBSD-NSE image.
Also, changes to other files to send out NSESWAP event.

One unrelated change: We now have per-swapin .top files and assign.log
files along with .ptop files. This helps in debugging across multiple
swapins since files remain in the form of
<pid>-<eid>-<process_id>.{top,ptop} and assign-<pid>-<eid>-<process_id>.log
Also useful for archiving.

but not other virt_* tables. Thats coz the above two tables are not
truly virtual since they contain the vnode to which the event should
be sent to. My previous patch has been to use replace instead of
insert. Unfortunately, the tables get messed up with the same agent
having multiple entries where some of the entries were left behind
from the previous swapin.

committed last, but this dump came out in a very different order, so the
diff looks huge, even though it is only about 8 lines.

added -eventsys_restart option to tbswap. These options are allowed
only with swapexp -s modify and correspondingly for tbswap with update.
Tested with a 1 node experiment and things seem to work fine.

of typing to log in to nodes, I wrote the same code in C.
Compile on cygwin with gcc -mwindows -mno-cygwin -o ssh-mime ssh-mime.c .
Set the env PUTTY_CMD to the path of where you have put putty. The compiled
exe is in http://www.emulab.net/ssh-mime.exe

you typed the URL directly instead of indirecting from the project
page. No one did that till today.

probably imperfect, but better then nothing. New option, "-t tag"
allows you to specify an arbitrary tag to match against the stated_tag
of the nodes table. The stated invocation will only operate on nodes
that match the tag, ignoring all events for other nodes. If
unspecified, stated will operate on all nodes with a NULL tag. This is
setup up at the beginning of time (or during a reload) saving the
per-node tag in the $nodes hash. Each time an event arrives, check the
tag in the table, ignoring the event if not a match.

On signaled reload() must also be careful to throw away timeouts from
the queue (and be careful not to set up new timeouts for ignored
nodes).  So, this allows you to set the tag for a node in the DB, and
then HUP stated so that it reloads it tables. That node will now be
ignored by that stated.

Also made some changes to debug mode. In debug mode, don't worry about
the pidfile or the lockfile or checking for other running stated
(which causes my debug version to exit! right away). Also, added a new
-l option to turn of syslog output and just send it all to stdout with
the debug output. -l can be only be used with -d of course.

So what can I do with all this:

	update nodes set stated_tag='lbs' where node_id='pc5';
	sudo kill -HUP `cat /var/run/stated.pid`
	sudo stated -d -l -t lbs

Which tells the main stated to ignore pc5. Then I run a debugging
stated that operates only on pc5. Later when done:

	update nodes set stated_tag=NULL where node_id='pc5';
	sudo kill -HUP `cat /var/run/stated.pid`

Which tells the main stated to operate on pc5 again.

when it cannot keep up with real-time.

bug: This affected encapsulated simulator packets that had to cross
multiple physical nodes before arriving at the destination simulator
traffic agent. This bug didnt affect live packets from traffic sources
on real PCs.

The NSESWAP event is now sent via the tevc command. The nse scheduler
waits for the slop factor (diff between clock and event dispatch time
that exceeds a threshold) to be crossed multiple times in a second
before sending the NSESWAP event. Currently 5 times in 1 second.
However, this needs more careful thought and will get modified later.
When is it really necessary to declare that an nse is overloaded?
i.e. what is the right slop factor? How many times can we tolerate
that the slop factor is exceeded to ensure end-to-end performance
is within a certain percentage of the expected?

number of times re-swapin has occured due to a simhost not being able
to keep up with real-time.

again.

One of the fixes changes the way in which we iterate through pclasses
in find_pnode(). We used to treat the vector like a ring buffer, and
start (randomly) someplace in the middle. This turns out to give some
bad statistical properties when doing dynamic pclasses, since long
chains of disabled pclasses will cause some pclasses to be selected
more often. My old hack of just hopping around randomly in the
disabled-pclass case was bad, because it's hard to tell when you've
actually tried all the pclasses - so, we were getting false negatives
where it was looking like there was no place available where we could
map a vnode, which turned out to have worse effects than I had
thought.

So, now, we make a list of all the indices and randomize the order,
then just iterate through that list.

We also now count the number of pclasses that are enabled at every
temperature step, and adjust the neighborhood size to remove them.
This makes dynamic pclasses quite a bit faster - it cuts the time
by 30% - 50% for my test case.

Cleaned up find_pnode() by removing some #ifdef's that we don't use,
and probably will never want to again - this makes the function almost
readable!

Well, thats the hope. Not sure it will work, but might as well try.

it to the user - it was a source of confusion.

debug problems.

in every routing table except the main before inserting new ones
obtained from tmcc. The problem was that even the interface routes
that were added when the interfaces were brought up are flushed.
Unfortunately these routes weren't getting added again.

The solution is to toggle the interfaces i.e. disabling and re-enabling
them again. It has the desired effect of flushing all the routes as well.
I'm not sure how things worked until now. In all my previous mappings
of the testbed/nse10 straight-line topology, things mysteriously worked!

Fix a bug in enum parsing

Fix typos that were keeping MySQL errors from coming through to the
web interface.

occur if a normal duplex link was created first. The reason is coz the
creation of an rlink would also internally create an IPTap agent and when
this agent was being attached to the node, classifier entries were being
added to the port demultiplexer for all the IP addresses of the simnode.
Unfortunately, if an rlink was created first before anything else, the
IP address would be set only in the next Tcl statement causing nse to
exit prematurely.

not skipped in the case of 10Mb 0ms links.

"upleavel 1 eval $script". The latter is wrong and was detected when a
for loop inside make-simulated did not work.

* use IP addr rather than finickey hostname when communicating with PLC.
* make Node._create() aware of "already assigned" condition.
* Bump vnode_setup timeout back to two minutes (for now).

keys. Previosly, I had based the create definition on the virt_nodes
table. Unfortunately, that turned out to be incorrect.

mechanism in the service sliver).

vnode_setup for the timeout on waiting for child processes.  I've
set it to 10 minutes since all ancillary setup programs have their own
time bounds (I think - the plab ones do anyway).

The function of plabmonitord has changed slightly.  Instead of setting
up and tearing down vnodes, its job is to just setup the emulab management
sliver on plab nodes in hwdown.  Once the vserver comes up and reports isalive,
it moves the node out of hwdown.  Currently, it first tries to tear down the
vserver before reinstantiating it.  In the future, we could get fancier and
try interacting with the service sliver directly before simply tearing it down.

All new plab nodes now start life in hwdown, and must be summoned forth
into production by plabmonitord.

This commit does NOT include support for the node-local httpd.  That will
come soon.

central.  Also, back out Mike's hack, and use the ALLOWED_LIST feature
Austin originally had to limit node scope.

some of the tables such as virt_agents and eventlist are not truly
virtual tables. That is coz they contain the vnode field which is
the same as the vname field in the reserved table. For simulated
nodes, the mapping may change across swapins and the event may have
to be delivered to a different simhost. Of course this problem
isn't there for jail vnodes or pc vnodes.