On Tue, Nov 22, 2011 at 9:11 PM, Jordan Otomo <[email protected]>wrote:
> Thanks Josh and Tom for the info. Tom, I was unable to profile my > flowgraphs using your suggested method. For some reason, the head block > does not predictably stop the program. For example, if I specify 15 items > it will return immediately (as expected), but if I use 16 items it will > hang. > That sounds like some work function isn't behaving correctly. Besides which, 16 items won't do you much good for profiling the timing. You'll need millions of samples to run long enough to get a good estimate. Tom > > On Nov 22, 2011, at 5:04 PM, Tom Rondeau wrote: > > On Tue, Nov 22, 2011 at 7:53 PM, Josh Blum <[email protected]> wrote: > >> >> >> On 11/22/2011 04:20 PM, Jordan Otomo wrote: >> > Hi, >> > >> > I'm having issues using the hier_block2. When I create a flowgraph >> > consisting of roughly 12 blocks, I don't get any overruns. However, >> > combining blocks (e.g. source -> hier_block2 -> sink) results in a >> > ton of overruns. The parameters of the individual blocks that have >> > been combined into the hier_block2 have not changed. Does the >> > hier_block2 wait for the work function of each of the blocks it >> > encompasses to return before producing outputs/requesting more >> > inputs? Any thoughts or advice would be greatly appreciated. >> > >> >> Your saying that a flow graph of *identical* topology has *different* >> performance when moving some of the blocks into a hier block? >> >> If thats the case, its hard to believe. The the flow graph is run, its >> essentially flattened. There is no difference to the scheduler or >> buffers whether or not hierarchical blocks were used. >> >> -josh > > > Yep, what Josh said. If this really is the case, though, it's definitely a > problem. Instead of using USRPs and looking at the overruns as your > benchmark, could you put in a signal source and a gr_head block of some > number of samples (10 to 100 million or so, enough to get a good > measurement) and switch out your sinks for null_sinks. Run the program and > time it between the non-hier block and the hier block version and let us > know what you get. > > Thanks, > Tom > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > >
_______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
