Running KStars/Ekos/Indi on my Raspberry Pi 4 headless as a WiFi hotspot, and linking in through VNC Viewer on an iPad. Most of the things I want to do work well (better not say ‘perfectly’!) but there are occasional crashes. Specifically in Polar Alignment I have been struggling to better see the reference star against the cross hairs at the end of the correction vector. I tried the ‘zoom to fit’ button in the Alignment Vector window, and this shut down KStars and Ekos, leaving behind ‘an Indi Server’ still running. Of course this means Parking the mount and running the process again.
I subsequently located the ‘full screen’ button in the main Alignment window, and found that this does change the size of the Alignment Vector window, but not the size of the image within it, although tapping a couple of times on the ‘zoom in’ button makes the Alignment Vector window content a good size for the adjustment operation.

I’m not sure if there’s a further bug in the way the Ekos ‘minimise window’ button also minimises the main KStars window?

Many thanks to the authors for this great software!

Are you using Ubuntu MATE or Buster to run KStars?
I have not had an issue with polar alignment, that seems to work flawlessly with KStars 3.3.6 on MATE, but I also experience the unexplained crashes. They do not happen when I run the same version of KStars on a mini-PC, so they must be Pi4 specific.
Basically that excludes my use of the Pi4 for the moment, since I usually run the rig unattended throughout the night.
Jo

Raspbian Buster in my case. The crashes only seem to occur when I am actively clicking on a button. When KStars minimises as I minimise Ekos, it is always possible to restore things from the Tab strip at the top of the screen.
Otherwise I haven’t suffered any random crashes, although I haven’t run any all night sessions like you.

Clicking the zoom to fit button in the align module has often resulted in kstars crashing for me. It seems to happen mainly with large dslr frames, and if I click the button while the image is being solved.

Edit: Pi4, 4gb in Raspbian Buster

I can trigger a Kstars crash by clicking the "toggle full screen" button, I haven't tried it for a while opting to use "default zoom" which doesn't cause the crash.

using NanoPC-T4 with Armbian Ubuntu Bionic

Same here, I usually crash when I click on the zoom buttons in the PA routine. INDI is still running but Kstars just shutdown and I have to launch it and then launch Ekos.

I am running StellarMate OS v1.4.4 for Raspberry Pi3B+ and DSLR

I can cause a crash by listing my regular gear and connecting to SM on Pi3 from a remote Windows machine, using phone as mobile hotspot; I use the regular profile, though no gear is connected- Setup, Scheduler, and Align modules appear in Ekos, and the former two are accessible, while the clicking on the Align module causes a crash. Setting profile to use CCD Simulator does not cause the crash. I realize this isn't priority, because I don't actually have devices connected, but it concerns me enough to list the purposeful crashing of KStars here. It would certainly be a problem when I do have devices attached and I'm trying to capture light.

I have the same problem running on pi3. I thought it was a memory problem but it happens still after I added 3Gb swap.
And the problem appears to happen more frequently when it's connected to the mount.

I also have that problema, using Stellarmate on a Raspberry pi 3b+.

While guiding and imaging, suddenly Kstars disappears but PHD2 continues guiding and Indi seems to remain connected.
After i restart Kstars and connect, a pop up window tells me that there is already an instance of Indi running. I chose to stop it and then Kstars can start workng again.

Greetings.

Looks to me this is a Raspberry Pi problem. It does not happen (or only very rarely) when I am running KStars on my Zotac mini-PC.
May be it running out of memory. I added 4 GB swap and that seems to have helped.

Yeah, If it happens on Raspberry PI and not on another computer, it probably is a memory issue. But if you can reliably produce a crash on different systems, we should see why it does crash.

NOTE: I wouldn't recommend a SWAP file on a raspberry pi due to issues with reading and writing of the SD card. You will wear it out. There is something much better called zram. Basically it takes the system ram, makes a compressed swap file for it, and puts the swap file in RAM instead of on the system disk. There is a slight performance hit since the system now has to do access compressed ram on a swap file in memory instead of just accessing memory. But the performance hit is worth the system not crashing. And it is also better than wearing out your SD card.

Hi Rob,

I can't "reliably" induce a crash of KStars, it seems to happen randomly to me, at least. The Zotac mini-PC I am using also has just 4 GB of RAM, but my Swap file there resides on the eMMC, not an SD card.
With respect to wearing out the SD card, I am less concerned about that. First, I had a swap file on my Pi3 and that was used extensively over the last year without any problem. The Swap file on the Pi4 so far appears to be used very sparingly (swappiness set at 20) and I put it only as a safeguard in case memory gets tight. Second, I don't know how to turn on zRAM in Ubuntu MATE on the Pi4. What is the procedure to do that? Third, microSD cards are really cheap now (I am using a 128 GB card from Samsung that costs $20 and it already last for over a year).
I actually ran my Pi4 without a hitch through the night 2 nights ago, but I did not use guiding. I have the suspicion that handing two cameras and other intensive tasks might be the problem. One of the crashes I had earlier occurred right during the meridian flip.