#3940 closed defect (worksforme)
Serious performance degradation on the latest Linux nightly builds (+50% build time)
| Reported by: | Francesco Casella | Owned by: | Martin Sjölund |
|---|---|---|---|
| Priority: | blocker | Milestone: | |
| Component: | Build Environment | Version: | |
| Keywords: | Cc: | stetrab@… |
Description
I have just re-run some tests on our power system models using the latest nightly OpenModelica 1.10.0~dev-701-ga54c8a3. The overall time to build the models has grown by about 50%(!!), spread among all compilation phases (front-end, back-end, simcode and templates).
I have talked to one of my co-workers, who's running experiments with the solar plant model, using the Linux nightlies. He also reports that using OpenModelica 1.10.0~dev-665-gc82690e (the nighly build of 25 May morning) he got a build time of about 400 seconds, while after updating to 1.10.0~dev-701-ga54c8a3 this morning, the build time has grown to 570 seconds, which is consistent with what I observed on the power system models. Unfortunately, I don't have any intermediate datapoints between those two nightlies.
I have double-checked the build time of the MSL coverage tests on Hudson between May 24 and May 30, but I cannot see this effect. On the contrary, the build time of the Engine V6 model went down from 45 seconds to 40 seconds between 26 May and 27 May and has stayed there since then.
So, I guess something went wrong with the build system, but honestly I couldn't say what it could be. Maybe some C compiler optimization gone astray? This could explain why all compilation phases are affected. Anyway, the loss of performance is quite severe.
Can you please have a look?
Change History (4)
comment:1 by , 8 years ago
comment:2 by , 8 years ago
| Resolution: | → worksforme |
|---|---|
| Status: | new → closed |
Update: the two Linux machines where this problem shows up run Ubuntu 14.04 and Ubuntu 16.04. After the last update, some tests on the 16.04 machine are back to normal, while on the 14.04 they're still slower. Maybe it was only a glitch in the Ubuntu updates.
I'll reopen this if other tests go bad on 16.04, I don't think we have to worry too much about older Linux installations.
comment:3 by , 8 years ago
I confirm that also the thermal power plant works as before on Ubuntu LTS 16.04 after the latest upgrades. We still have the problem with LTS 14.04, but I guess the fix there is easy (-> upgrade the OS).
For your model, translateModel(E):
-O2 -g)(I tested the old version by downloading the corresponding deb-packages for the old package and using dpkg -i to install them)
Did your virtual server get a new occupant using resources or some other changes? If you install c82690e again, do you get the old better performance back as well?