SNAP 8 slow opening and UI errors

Dear SNAP developers,

I appreaciate a lot SNAP 8. Thanks for your continuous efforts in help the EO community.

I’d like to point out issues I face during the use of SNAP 8 I encounter.

The first and most urgent issue is the very low start of SNAP. The icon launches, then it is stucked at “Done loading modules” for about 5-10 MINUTES. Then, out of nowhere, SNAP is there. I’m a bit surprised about that and I have no idea what explains that.

The second is small visual artifacts, like the figure here :

As you can see, the bottom boxes are slighlty cut (we cannot distinguish clearly the values). in addition, some texts are hidden, such as “Cache Size (…”. Changing the window size doesn’t free the missing text.

The visual artifacts are small UI bugs that are probably to be expected in a Java app:

  • the “Cache Size (…” label should say “Cache Size (MB)”, but it’s too narrow and the text is ellipsized; making the window larger doesn’t fix it because of the way the layout is done in that screen, but amusingly, you can make the window smaller and the text will show up (only in the Metal Look And Feel, not in GTK+):

  • you’ll also noticed that the cut-off text doesn’t happen with Metal; it happens on GTK+ because the text is larger and the control has a fixed height
  • you’ll probably find that Metal LAF better if these small UI bugs bother you

As for your original problem, unfortunately there’s no “don’t load in 5 minutes” checkbox in the Performance settings. Other users haven’t complained about the loading times, so it might be something specific to your setup:

  • if you’ve got a system-wide install (in /opt/snap), you could try uninstalling SNAP and installing it again
  • you could reset the SNAP settings by removing ~/.snap – the GTK+ LAF isn’t the default, so it’s using some custom settings
  • if you’ve installed updates as root, SNAP might try to reinstall them on every restart; deleting /root/.snap might be a good idea too
  • if you have any broken network mounts, it might be trying to read something from them
  • I would go as far as to create a new system user, then run SNAP from there

If none of the above helps, there are a couple more steps you could take to see what it’s doing:

  • run htop to check CPU and RAM usage (maybe the heap size is misconfigured and it’s writing tens of GBs in the swapfile)
  • attach strace -f (sudo strace -fp $(pidof java), probably, but see to it to see what system calls are running
  • use perf to see if it’s spending time in C or kernel code: take a look at
  • try the Java tools (e.g. jstack) to get a stack trace of the Java threads
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The visual artifacts can be fixed by changing the “skin” of your GUI. I don’t remember which ones surely work, @marpet do you?

I think it’s

the GUI theme.

Do you have SNAP configured to check for updates at startup? For me there is a short delay after “Done loading modules” before SNAP opens and displays a Plugin Installer panel with “There are no updates available”. Network problems could explain the delay your are seeing.

Thank for you answer. I’ll go into each of your recommendations and go back to you.

Hi all,

Just to give a feedback, i finally managed to tackle my issues. Changing the theme corrected the UI issue, as advised by @lnicola.

To correct SNAP, I had to delete every piece of SNAP file present on my computer and perform a full reinstallation. Now everything is clean is seems to work properly. Not exactely sure what happened, but years of installing softwares / libraries probably messed up something in my computer.

Thanks for your help


Hi, just for feedback, I faced the same problem. the interface was very slow, reacting like 10sec after each clic…
A complete reinstallation (cleanning users data) fixed that.

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