Re: [Dorset] Debugging issue with lightdm display manager on old laptop
On 09/06/2020 18:15, Ralph Corderoy wrote: > Hi Hamish, > > If it's oldish hardware then > https://forum.sparkylinux.org/index.php?topic=4195.0 suggests it could > be your choice of theme which is taxing the X server. I expect the > hardware's resources can be overwhelmed by the requirements and normal > hardware methods get switched to software. Or something. > > launchpad.net used to have a very annoying bug where they put all their > little icons into one very tall PNG, tens of thousands of pixels tall, > which Firefox then tried to give to the Nvidia graphics driver. It > ‘worked’, but caused a delay of many seconds, making the web site > unusable. Both Firefox and Nvidia were required to trigger. > Yeah, it's a low end laptop from 2012, so pretty old. That would make sense. Interesting example. Either way, I haven't seen the problem on any newer/different hardware and given my trackpad isn't working I now wonder if my hardware's just toasted XD. Hamish signature.asc Description: OpenPGP digital signature -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
Re: [Dorset] Selling GPL software with different price points.
On 09/06/2020 18:39, Patrick Wigmore wrote: > On Mon, 08 Jun 2020 15:43:32 +0100, Hamish McIntyre-Bhatty wrote: >> I don't think I have a way of enforcing that people buy the correct >> version for business, but I could always just have a "Personal Use" >> notice in the title bar or something. > I don't think you can place a restriction like "personal use only" on > how the GPL-licensed software is used. GPL is GPL. > > You could in principle distribute a different version of the software > depending on which fee is paid, but I think it would be invalid to > distribute a version with a notice saying "Personal Use", because that > implies a restriction that's not in the license. At best it's > misleading. > > If you want to apply limitations, then I think you might have to > distribute the business version of the software, or some components of > it that don't appear in the "personal" version, under a different > license. Doing so may or may not be allowed, depending on any > restrictions you may have agreed with third parties. (e.g. code > contributors, library authors, others?) > Point taken. Instead I'll maybe just have a higher support tier or something eg priority email support if you pay a little bit more. I'll come up with something that seems reasonable anyway, but cheers because I might not have thought of that without your input :) Hamish signature.asc Description: OpenPGP digital signature -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
Re: [Dorset] Selling GPL software with different price points.
On Mon, 08 Jun 2020 15:43:32 +0100, Hamish McIntyre-Bhatty wrote: > I don't think I have a way of enforcing that people buy the correct > version for business, but I could always just have a "Personal Use" > notice in the title bar or something. I don't think you can place a restriction like "personal use only" on how the GPL-licensed software is used. GPL is GPL. You could in principle distribute a different version of the software depending on which fee is paid, but I think it would be invalid to distribute a version with a notice saying "Personal Use", because that implies a restriction that's not in the license. At best it's misleading. If you want to apply limitations, then I think you might have to distribute the business version of the software, or some components of it that don't appear in the "personal" version, under a different license. Doing so may or may not be allowed, depending on any restrictions you may have agreed with third parties. (e.g. code contributors, library authors, others?) -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
Re: [Dorset] Debugging issue with lightdm display manager on old laptop
Hi Hamish, If it's oldish hardware then https://forum.sparkylinux.org/index.php?topic=4195.0 suggests it could be your choice of theme which is taxing the X server. I expect the hardware's resources can be overwhelmed by the requirements and normal hardware methods get switched to software. Or something. launchpad.net used to have a very annoying bug where they put all their little icons into one very tall PNG, tens of thousands of pixels tall, which Firefox then tried to give to the Nvidia graphics driver. It ‘worked’, but caused a delay of many seconds, making the web site unusable. Both Firefox and Nvidia were required to trigger. -- Cheers, Ralph. -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
Re: [Dorset] Debugging issue with lightdm display manager on old laptop
On 09/06/2020 12:26, Ralph Corderoy wrote: > I'd start with these two. The bug is probably LightDM's, e.g. it's > repeatedly asking Xorg to do some work on its behalf, though it might be > it's making a reasonable request which Xorg is doing inefficiently and > SDDM doesn't make the same request. I doubt it's the latter though > because Xorg is prodded by a lot of different client and a problem would > have already come to light. > > So, concentrating on LightDM, see if it has debug which you can enable > and find the output in the logs or journal. This might be the easiest > way to spot the problem, e.g. it's unhappy a file is missing. Ensure > the problem is occurring at the time, e.g. high CPU use. > > Next step would be to attach to it's running processes with strace(1) to > see what it's doing. ‘systemctl status lightdm.service’ will probably > show multiple process IDs to choose from, but not display the PIDs for > its threads. One way to obtain all of them is ‘sudo lsof > /usr/bin/lightdm’. > > Given those PIDs, ‘sudo strace -fp '42 314 1718'’ will attach to all of > them and any new children. You'll hopefully see they're all blocked, > i.e. consuming no resources. Many will be blocked on a file descriptor. > ‘sudo lsof -p 42’ will lists the FDs of PID 42, out of interest. > > Type a character into LightDM and see if it creates a flurry of > syscalls. They should die down to idle again. If not, there's your > clue. It might be sending a request to the Xorg X server over and over. > > strace's output can be stuffed to a file with -o instead of scrolling up > the screen. -e will let you filter out boring system calls, or > concentrate on particular ones, e.g. the ‘%desc’ set. > > Happy hunting! Cheers for the advice. I just went about reinstalling lightdm on the thing, but it turns out that it doesn't work at all now, and also my trackpad doesn't work either, so, erm... I think I'll leave this one seeing as I no longer have any confidence that the hardware even still works properly, though it's probably more driver issues. I guess I could reinstall Mint, but for its current purpose (computing for Rosetta) the laptop is working okay so it's probably not a productive use of time. Hamish signature.asc Description: OpenPGP digital signature -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
Re: [Dorset] Debugging issue with lightdm display manager on old laptop
Hi Hamish, > - Xorg, seeing as it's what's using lots of CPU power. > > - LightDM, seeing as the issue only occurs when I use LightDM. I'd start with these two. The bug is probably LightDM's, e.g. it's repeatedly asking Xorg to do some work on its behalf, though it might be it's making a reasonable request which Xorg is doing inefficiently and SDDM doesn't make the same request. I doubt it's the latter though because Xorg is prodded by a lot of different client and a problem would have already come to light. So, concentrating on LightDM, see if it has debug which you can enable and find the output in the logs or journal. This might be the easiest way to spot the problem, e.g. it's unhappy a file is missing. Ensure the problem is occurring at the time, e.g. high CPU use. Next step would be to attach to it's running processes with strace(1) to see what it's doing. ‘systemctl status lightdm.service’ will probably show multiple process IDs to choose from, but not display the PIDs for its threads. One way to obtain all of them is ‘sudo lsof /usr/bin/lightdm’. Given those PIDs, ‘sudo strace -fp '42 314 1718'’ will attach to all of them and any new children. You'll hopefully see they're all blocked, i.e. consuming no resources. Many will be blocked on a file descriptor. ‘sudo lsof -p 42’ will lists the FDs of PID 42, out of interest. Type a character into LightDM and see if it creates a flurry of syscalls. They should die down to idle again. If not, there's your clue. It might be sending a request to the Xorg X server over and over. strace's output can be stuffed to a file with -o instead of scrolling up the screen. -e will let you filter out boring system calls, or concentrate on particular ones, e.g. the ‘%desc’ set. Happy hunting! -- Cheers, Ralph. -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
[Dorset] Debugging issue with lightdm display manager on old laptop
Hi, I probably mentioned a while back at a meeting that my laptop had a problem where sometimes (seemingly unpredictably) one CPU core would be locked at 100% by Xorg after booting up. Eventually, I realised that changing my display manager from LightDM to SDDM fixed the issue, but I never found out what the cause was. I reported it but no one seems particularly interested in fixing it. I've never even attempted to debug something like this, so I was wondering if any of you could help/offer suggestions for where to start. Problem is, I see quite a lot of places to look, and I've never even used a debugger XD. I'm guessing the potential problem areas could be: - The display driver (the older Radeon driver used for older AMD/ATI graphics chips) - Xorg, seeing as it's what's using lots of CPU power. - LightDM, seeing as the issue only occurs when I use LightDM. - My hardware (perhaps this could all be because of a hardware fault?) Has anyone got any experience of dealing with these kinds of problems? I should note that I'm satisfied with my workaround, so it's not at all important to me that this gets fixed, I just thought it might be interesting to look at. Hamish signature.asc Description: OpenPGP digital signature -- Next meeting: Online, Jitsi, Tuesday, 2020-07-07 20:00 Check to whom you are replying Meetings, mailing list, IRC, ... http://dorset.lug.org.uk New thread, don't hijack: mailto:dorset@mailman.lug.org.uk
