On Fri, Jul 8, 2016 at 2:35 PM, David Medine
Hello, I am an engineer in a neurosciences lab. We have some data acquisition software that uses boost::thread and some other boost libraries as well. Part of my job is to measure the lag time for our devices' data acquisition. I have been testing the acquisition software when linking against boost v.1.57.0 and v.160.0.
10 ms is pretty good on a non-r/t OS such as Windows, much less Windows 7 (basically, Vista core). You're sure you're building against release and not debug mode?
Basically I generate a test signal and read it in with an NIDAQ and our EEG system. The signal is a series of 3ms long pulses. When the input to the NIDAQ goes high, I generate a timestamped marker. Meanwhile the EEG system is getting the same pulse train input and I record that digital data on its own thread and timestamp that as well. Then I compare the timestamps at which the EEG signal has a rising edge with the timestamps of the markers. The difference between these time values is the lag of the EEG system.
The app I use to get the EEG signal uses boost::thread. The lag time is consistently ~2.7 ms when linking against boost v.1.57.0 and is a whopping 11.6 ms when I link against v.1.60.0. Since the data acquisition happens in a tight loop on its own thread, I am guessing that there is some kind of increased latency of boost threads in newer versions of the library.
Does anybody know what might be causing this? I am on Windows 7, 64-bit and am using the pre-compiled boost libraries (i.e. I am not compiling them myself).
Cheers, David _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users