# Is there a way to know the progress of compilation?

**URL:** <https://brian.discourse.group/t/is-there-a-way-to-know-the-progress-of-compilation/1425>\
**Category:** Support\
**Tags:** cpp\_standalone\
**Created:** [24 March 2025 07:56 UTC](https://brian.discourse.group/t/is-there-a-way-to-know-the-progress-of-compilation/1425 "2025-03-24T07:56:22Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Jasmine9691](https://yyz2.discourse-cdn.com/free1/user_avatar/brian.discourse.group/jasmine9691/32/811_2.png) [@Jasmine9691](https://brian.discourse.group/u/Jasmine9691)\
**Post date:** [24 March 2025 07:56 UTC](https://brian.discourse.group/t/is-there-a-way-to-know-the-progress-of-compilation/1425/1 "2025-03-24T07:56:22Z")

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# Description of problem

Hi, all. This topic is a continue of [How to compute the time-average values on the fly? - #9 by Jasmine9691](https://brian.discourse.group/t/how-to-compute-the-time-average-values-on-the-fly/1356/9).

Now my model has over 160 equations, hundreds of neurons and synapses. It takes me really a LONG time to compile using no matter cython or cpp\_standalone. One hour has passed but the compilation has not been completed. I wonder

1. whether there is a way to know the progress of compilation, so that I can know how much time I have to wait for.
2. whether there is a way to accelerate the compilation, e.g., something like `make -j8`.

Thanks in advance!

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**Author:** ![Jasmine9691](https://yyz2.discourse-cdn.com/free1/user_avatar/brian.discourse.group/jasmine9691/32/811_2.png) [@Jasmine9691](https://brian.discourse.group/u/Jasmine9691)\
**Post date:** [24 March 2025 13:14 UTC](https://brian.discourse.group/t/is-there-a-way-to-know-the-progress-of-compilation/1425/2 "2025-03-24T13:14:46Z")

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I compiled step by step, and found this could be faster (1-3 minutes).

For example, my full code is

```python
A = NeuronGroup(10, eqs_A)
B = NeuronGroup(20, eqs_B)
S = Synapses(A, B, on_pre=eqs_S)
...
net = Network(A,B,S,...)
net.run(10*ms)

```

Compiling this code should have been much too time-consuming.

I first compiled only A and commented others:

```python
A = NeuronGroup(10, eqs_A)
#B = NeuronGroup(20, eqs_B)
#S = Synapses(A, B, on_pre=eqs_S)
#...
net = Network(A)
net.run(10*ms)

```

This compilation took \< 10 second.

Then I uncommented B and added it to the `net`:

```python
A = NeuronGroup(10, eqs_A)
B = NeuronGroup(20, eqs_B)
#S = Synapses(A, B, on_pre=eqs_S)
#...
net = Network(A, B)
net.run(10*ms)

```

This compilation also took \< 10 second.

Similarly, I uncommented other objects and compiled them step by step. And the total compilation took me only 1-2 minutes. During the process, some bugs (e.g., some identifiers cannot be resolved) were also quickly detected and resolved. I guess they could also have slowed down the compilation. To validate this, I `clear_cache('cython')` after all the bugs were fixed, and found that the compilation took only 3 minutes.

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**Author:** ![mstimberg](https://yyz2.discourse-cdn.com/free1/user_avatar/brian.discourse.group/mstimberg/32/11_2.png) [@mstimberg](https://brian.discourse.group/u/mstimberg)\
**Post date:** [25 March 2025 15:54 UTC](https://brian.discourse.group/t/is-there-a-way-to-know-the-progress-of-compilation/1425/3 "2025-03-25T15:54:57Z")

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Hi, for Cython, I don’t see a way to get feedback on the compilation progress without changing Brian’s package source code manually. For C++ standalone, you can give extra arguments to the make command (note that it already passes `-j` on Linux/macOS by default). You’ll also need to switch on debug mode since otherwise all output is suppressed. E.g. you can use:

```python
set_device('cpp_standalone', debug=True)
prefs.devices.cpp_standalone.extra_make_args_unix += ['--debug=bj']

```

But compilation – especially with Cython – will always be slow if you have many objects. Given that you state that you have “160 equations, hundreds of neurons and synapses”, I am pretty sure that you can drastically reduce this number by putting together groups of neurons that share the same basic equations, and only differ in parameters. You can always use _Subgroups_ (i.e. `neurons = NeuronGroup(...); group1 = neurons[0:10]; group2 = neurons[10:20]` etc.). This will drastically reduce the time for compilation, since every `NeuronGroup` results in between 1 and 3 files that each need to be compiled individually, and similar for `Synapses`.

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<div class="post-metadata">

**Author:** ![Jasmine9691](https://yyz2.discourse-cdn.com/free1/user_avatar/brian.discourse.group/jasmine9691/32/811_2.png) [@Jasmine9691](https://brian.discourse.group/u/Jasmine9691)\
**Post date:** [26 March 2025 02:14 UTC](https://brian.discourse.group/t/is-there-a-way-to-know-the-progress-of-compilation/1425/4 "2025-03-26T02:14:02Z")

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Hi @mstimberg . Thanks for you kind suggestions. I tried subgroups with same equations and parameters but different synaptic connections. It indeed speeded up the compilation and a bit simulation. Also, I could intialize all the subgroups together, which saved dozens lines of my code.