# GRC Reacting Slowly **URL:** \ **Category:** GNU Radio\ **Created:** [May 27, 2015, 1:10am UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099 "2015-05-27T01:10:27Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Detlef\_R](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/58f4c7/32.png) [@Detlef\_R](https://www.ruby-forum.com/u/Detlef_R)\ **Post date:** [May 27, 2015, 1:10am UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/1 "2015-05-27T01:10:27Z")
GNU Radio 3.7.8, Ubuntu 14.04 I have an admittedly large number of blocks in my current flow graph because I’m in the middle of some hardcore debugging. Every time I select a block to enable/disable it, there is a \> 2 second delay between the block becoming enabled/disabled and hitting the E/D keys. The same is true when connecting new ports together with wires. I’ve been working with this for a while, but it’s annoying enough now that I’d like to know if there is a workaround to this or simply understand the cause of it? v/r, Rich ---
**Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 27, 2015, 5:14pm UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/2 "2015-05-27T17:14:47Z")
Hi rich, on which hardware platform are you working ? Is this a PC or embedded device ? cheers, Andy Am 27.05.2015 um 01:09 schrieb Richard B.: ---
**Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 27, 2015, 9:10pm UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/3 "2015-05-27T21:10:19Z")
I had this problem for a while when using a large number of blocks. The cause, I think, is that the companion checks if the flowgraph is correct after every change. You will only be able to compile if it’s correct (blocks are connected, variable names exist…). If this is really the reason, It would be nice to have an icon that, when unselected disables this check and when selected it checks the flowgraph and enables the compile and run options if everything is ok. Regards, Murray 2015-05-27 16:08 GMT+01:00 Andreas L. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): ---
**Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 28, 2015, 9:06am UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/4 "2015-05-28T09:06:49Z")
Hi Richard, I’ll pitch `perf` here (you’re on Ubuntu, so it’s in the linux-tools, probably). Build GNU Radio with the debugging symbols enabled, i.e. call CMake with the build type specified: cmake -DCMAKE\_BUILD\_TYPE=RelWithDebInfo … Then, allow normal users to sniff around processes’ calls: sudo sysctl kernel/perf\_event\_paranoid=-1 Run GRC to see where time is spent (-a is for “all CPUs”) perf record -a gnuradio-companion play around in GRC. Close it and interpret the result as shown by perf report Greetings, Marcus ---
**Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 28, 2015, 6:37pm UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/5 "2015-05-28T18:37:18Z")
On Thu, May 28, 2015 at 12:05 AM, Marcus Müller [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I’ll pitch `perf` here (you’re on Ubuntu, so it’s in the linux-tools, > probably). I’m pretty sure the issue is as Murray T. described above. We’ve had to optimize this area in the past in GRC. ---
**Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 28, 2015, 1:18am UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/6 "2015-05-28T01:18:43Z")
Andreas, No I’m not using an embedded system to develop on. I’m using an HP Core i7 laptop with 16Gig of RAM, Ubuntu 14.04 with GNU Radio 3.7.8. The delay also occurs everytime I want to make a change to a blocks paramters. I have to wait \>2 seconds for the blocks paramter window to open and then another \>2 seconds for it to close. It all adds up. If the reason is what Murray said, I would agree it would be nice to have the option of checking only when you click the play button or something similar. v/r, Rich On Wed, May 27, 2015 at 12:08 PM, Murray T. \ **Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 29, 2015, 3:35pm UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/7 "2015-05-29T15:35:02Z") Hi Murray, thats an interesting fact. My project has a lot (i didnt count them) of blocks. I have the same delay problem on my PC and on my embedded device. On the embedded device its slower than on my pc 🙂 If i use only a few blocks than the delay is short. So i think your theory and suggestion is great. Andy Am 27.05.2015 um 21:08 schrieb Murray T.: ---
**Author:** ![reback](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/b5ac83/32.png) [@reback](https://www.ruby-forum.com/u/reback)\ **Post date:** [May 29, 2015, 4:40pm UTC](https://www.ruby-forum.com/t/grc-reacting-slowly/242099/8 "2015-05-29T16:40:27Z")
Hey, so, I timed the flowgrah update steps rewrite, validate, create labels, create shapes and it turns out most time is actually spent in validate. However, for some reason the validate step currently performs the evaluation of the params and this is also where it spends almost all of its time. So, moving this to rewrite and making validate optional is certainly possible, but doesn’t help (because then validate takes no time to run). Further profiling is required. Sebastian