Hi Kristof, thanks for the fast reply. So basically I used a stopwatch to measure the startup time ... :-o
But for comparison I now used the same command as you and got the following results: (1) real 2m14.390s user 0m51.370s sys 0m7.200s (2) real 1m46.367s user 0m39.700s sys 0m6.890s (3) real 1m46.623s user 0m40.120s sys 0m6.470s (4) real 1m46.275s user 0m39.860s sys 0m6.770s Meanwhile I also checked the file system accesses with strace of the process and verified, that my buffering on my tmpfs RAM disk works as intended. Bad news about it is of course, that obviously the Galileo board is just too slow for ROS :-( Thanks for sharing your data with me! Best regards Christoph Am Samstag, 7. Dezember 2013 09:52:42 UTC+1 schrieb Kristof Robot: > > Hi Christoph, > > Which commands are you using to measure performance? > > Measuring the startup time of roscore on my Cubieboard2 (ARM Cortex-A7 > dual core, 1GB RAM with SanDisk 16GB SDHC Class 10 UHS-1 SD card), I get: > > *Command used: > time sh -c '(roscore &); until rostopic list;do echo "."; done' > > *Results (four times run: first after cold boot, three others after having > killed the roscore process manually): > (1) > real 0m32.947s > user 0m26.700s > sys 0m3.410s > > (2) > real 0m22.525s > user 0m18.260s > sys 0m2.390s > > (3) > real 0m22.560s > user 0m18.760s > sys 0m2.060s > > (4) > real 0m21.827s > user 0m17.980s > sys 0m2.320s > > This surely is not the best way to accurately measure performance, but it > gives some idea. > > If you let me know which measuring commands you are using, I'd be happy to > share the results of those on my hardware. > > Thanks, > > Kristof > > > > On Thu, Dec 5, 2013 at 10:58 PM, Christoph Schultz > <schul...@gmail.com<javascript:> > > wrote: > >> Hi group, >> >> I recently joined the group, because I downloaded the meta-ros layer and >> wanted to share my experience with ROS on an OpenEmbedded Linux. The >> initial compilation went through without any serious issue. So good job :-) >> After installing all required packages I could finally start roscore on my >> Galileo board. Unfortunately there I ran into some serious performance >> limitations. Booting roscore on my EeePC (I use for prototyping) requires >> only some seconds. On the Galileo board it took me more than a minute, so I >> ran into a timeout. This I could finally avoid by adapting the py-script, >> but even when roscore started afterwards I could not query any topics or do >> anything with my running ROS. >> >> One bottleneck was easily identified to be the SD-card connected to the >> Quark-CPU. I tried to shift all required files to a tmpfs into RAM and >> could achieve a significant speed boost. Unfortunately it is still too slow >> to be usable. >> >> I would be interested in the performance level of your hardware you are >> using ROS with. Best case would be, that I finally find out that I just >> forgot to move some important files to my tmpfs, so I am facing still the >> same bottleneck. Worst case would of course be, that the CPU performance is >> just not sufficient for this python based environment... >> >> Some HW stats of my OpenEmbedded System: >> >> 400 MHz x86 Quark CPU >> 256 MB RAM >> 8 GB SD card >> >> Regards >> Christoph >> > >
