It is an excellent platform for catching bugs: big-endian, slow enough
that a context switch in the middle of an operation becomes a regular
occurrence, and all that on a SMP box. Or: I just wanted to see if it
would work.
Signed-off-by: Erik Boasson <eb@ilities.com>
Tracking pings and expected number of pongs was done without holding the
correct locks. Terminate flag was also not a ddsrt_atomic... and hence
flagged by thread sanitizer as a race condition.
Signed-off-by: Erik Boasson <eb@ilities.com>
* Remove dds_return_t / dds_retcode_t distinction (now there is only
dds_return_t and all error codes are always negative)
* Remove Q_ERR_... error codes and replace them by DDS_RETCODE_...
ones so that there is only one set of error codes
* Replace a whole bunch "int" return types that were used to return
Q_ERR_... codes by "dds_return_t" return types
Signed-off-by: Erik Boasson <eb@ilities.com>
* As a simple matter of code hygiene, in particular to aid in checking for
leaks, ddsperf should free all memory it allocates on exit.
* Remove spurious mutex unlock in ddsperf
* Removing a participant means removing one or two entries from the "pong
writers" array ("pong wr"), and there it read 1 element beyond the end
of the array while moving the remaining elements forward.
* Constant-rate pinging was broken because of two reasons, one worse than
the other:
* setting the rate had a mismatch in variables (publication rate and
command-line argument) resulting in a completely wrong ping interval;
the code now has a bit more clear variable naming ...
* the timing of the pings was relative to the current time, but the
wakeup a little delayed, resulting in a lower rate than requested.
It now simply adds the ping interval to the scheduled ping time, rather
than the time at which the ping is being sent. To guard against really
late wakeups, rates that are too high, suspending the machine, &c. it
will in extremis delay the next ping.
Signed-off-by: Erik Boasson <eb@ilities.com>
Multiplying time-in-ns since previous output line by 1e9 instead of
dividing it by 1e9 resulted in bit rate showing up as 0Mb/s.
Signed-off-by: Erik Boasson <eb@ilities.com>
The current situation for performance measurements and checking network
behaviour is rather unsatisfactory, as the only tools available are
``pubsub`` and the ``roundtrip`` and ``throughput`` examples. The first
can do many things thanks to its thousand-and-one options, but its
purpose really is to be able to read/write arbitrary data with arbitrary
QoS -- though the arbitrary data bit was lost in the hacked conversion
from the original code. The latter two have a terrible user interface,
don't perform any verification that the measurement was successful and
do not provide the results in a convenient form.
Furthermore, the abuse of the two examples as the primary means for
measuring performance has resulted in a reduction of their value as an
example, e.g., they can do waitset- or listener-based reading (and the
throughput one also polling-based), but that kind of complication does
not help a new user understand what is going on. Especially not given
that these features were simply hacked in.
Hence the need for a new tool, one that integrates the common
measurements and can be used to verify that the results make sense. It
is not quite done yet, in particular it is lacking in a number of
aspects:
* no measurement of CPU- and network load, memory usage and context
switches yet;
* very limited statistics (min/max/average, if you're lucky; no
interesting things such as jitter on a throughput test yet);
* it can't yet gather the data from all participants in the network
using DDS;
* it doesn't output the data in a convenient file format yet;
* it doesn't allow specifying boundaries within which the results
must fall for the run to be successful.
What it does verify is that all the endpoint matches that should exist
given the discovered participant do in fact come into existence,
reporting an error (and exiting with an exit status code of 1) if they
don't, as well as checking the number of participants. With the way the
DDSI protocol works, this is a pretty decent network connectivity check.
The raw measurements needed for the desired statistics (apart from
system-level measurements) are pretty much made, so the main thing that
still needs to be done is exploit them and output them. It can already
replace the examples for most benchmarks (only the 50%/90%/99%
percentiles are still missing for a complete replacement).
Signed-off-by: Erik Boasson <eb@ilities.com>
