Benjamin Poirier
benjamin.poirier@polymtl.ca
-2009
+2009, 2010
+ About time synchronization
This framework performs offline time synchronization. This means that the
event_analysis_chull.h.
+++ Linear Regression
-linreg sometimes gives more accurate results than chull but it provides no
+linreg sometimes gives more precise results than chull but it provides no
garantee
+++ Synchronization evaluation
it calculates and prints different metrics about how well traces are
synchronized. Although it can be run like other analysis modules, it is most
useful when run in a postprocessing step, after another synchronization module
-has been run. Eval is most common run in text mode. To do this, run
-lttv -m eval [usual options, ex: -t traces/node1 -t traces/node2 --sync ...]
+has been run. Eval is most commonly run in text mode. To do this, run:
+lttv -m sync_chain_batch [usual options, ex: -t traces/node1 -t traces/node2
+--sync ...]
+It can also be run from the lttv source tree via runlttv:
+./runlttv -m eval [usual runlttv options, ex: traces/node1 traces/node2]
eval provides a few more options:
--eval-rtt-file - argument: FILE
Many commands can be used to measure the RTT, for example:
ping -s 8 -A -c 8000 -w 10 192.168.112.57
-Note that this must be repeated in both directions in the file.
+Note that this must be repeated in both directions in the file, that is:
+192.168.112.49 192.168.112.50 0.057
+192.168.112.50 192.168.112.49 0.050
++++ Linear Programming and GLPK
The synchronization evaluation can optionally perform an analysis similar to
the graph output).
This is enabled by default at configure time (--with-glpk) if the GNU Linear
-Programming Kit is available (libglpk).
+Programming Kit is available (libglpk). On Debian-like systems (ex. Ubuntu),
+install the package "libglpk-dev".
+
+To see the output of this mode, run:
+lttv -m sync_chain_batch --eval-graphs [usual options, ex: -t traces/node1 -t
+traces/node2 --sync ...]
+ Design
This part describes the design of the synchronization framework. This is to
will require some modifications. It is already partly supported at the
matching stage through encapsulation of other matching modules.
-sync_chain_unitest provides a fairly simple example of sync chain
+sync_chain_unitest:main() provides a fairly simple example of sync chain
implementation.
++ Stage 1: Event processing