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100% cpu usage

Posted: Wed Jan 26, 2022 3:10 pm
by nicokid
Hi,
I have been using qcad for some time on linux ubunti 18.04. Today I have to open a large 96Mb dwg file.
Unfortunately the program is very slow and one of the 12 CPUs is 100%
I have read that since release 3.24.0 qcad uses multithreading on multiple cpu. But using the "top" command I always see only one cpu used by qcad
Is there any way to solve this problem? Or is it possible to convert the dwg file to a less difficult format for qcad?

Thanks.

Re: 100% cpu usage

Posted: Wed Jan 26, 2022 8:35 pm
by Husky
nicokid wrote:
Wed Jan 26, 2022 3:10 pm
Today I have to open a large 96Mb dwg file.
Unfortunately QCAD is not build to handle 96Mb files. There is not a fix threshold but files around 10 - 20 Mb are already a big deal for QCAD ... :wink:
nicokid wrote:
Wed Jan 26, 2022 3:10 pm
Or is it possible to convert the dwg file to a less difficult format for qcad?
I haven't seen the file but most likely - no. I assume there are a lot of hatches and maybe overkill blocks in the drawing. To make it more workable you can try to transfer those "things" to a dedicated layer and turn it to invisible. Other possibility would be to divide the drawing into e.g. 10 drawings ... I don't know how practical that would be ...

Re: 100% cpu usage

Posted: Thu Jan 27, 2022 7:59 am
by CVH
Husky,

A file does not grow only because of many hatches.

A hatch is just an entity, defined with a boundary as a polyline and a named pattern.
The pattern itself is also included. These are usually small.
Together they don't take up much space in a dwg file.

Problematic hatch patterns or a large origin offset or the scale of things may slow down rendering under QCAD ... After a file is loaded.

The use of blocks may even decrease size.

But indeed, a 96 MB (binary) dwg file will contain a vast amount of entities.
Hidden or not.
A 100Mb dxf file is usually not a problem.

Finally 'Auto save' can be problematic as that uses the dxf format.

Regards,
CVH

Re: 100% cpu usage

Posted: Fri Jan 28, 2022 10:26 pm
by nicokid
Ok, thanks for the answer.
The dxf files are text files and unfortunately they are too big :cry:
Unfortunately this is a factory layout consisting of several machines. It was built by taking the technical drawings of the machines and putting them together.
None of the designers are concerned with simplifying and rationalizing the layouts. Always the same problem with everyone. :evil:

Nicola.

Re: 100% cpu usage

Posted: Sat Jan 29, 2022 3:56 am
by CVH
Nicola,

Agreed ... The exact rendering of every 3mm nut won't make any sense on a factory layout :lol:

Only CAD has evolved to a level that this can be.
One could render every single fiber in a Airbus A380plus its carpets.
And that comes at a price. :wink:

Regards,
CVH