josm-latest is very slow after updating Opensuse Tumbleweed

[anonymous]

What steps will reproduce the problem?

Today I updated my opensuse Tumbleweed. Last update was Apr 25.
Before the update, in the morning I was editing with JOSM without noticing any problem.
Reboot required, so I closed JOSM and reboot.

When JOSM started it suggest updating to a new latest, so closed it, downloaded josm-latest.jar (19396) and restarted it.

It was impossible to work again.
JOSM started very slow, not sure in which stage.
When clicking in File-Download data i have to wait aprox 10 seconds before the Download window appears.
After downloading data, when I select a way or node, the UI is not responsive anymore for a lot of seconds, no matter if the element was selected by clicking on it or in the element list in the right dialogs panel.

Then I also tried with older JOSM snapshots, but the problem persist, so i thinked maybe it is related to Opensuse update. I'm running it in KDE Wayland with the options shown below.
Then the problem dissapeared when adding the option to enable 2D graphic accelerators -Dsun.java2d.opengl=true
and then i was unable to reproduce it, it works fine with or without graphic accelerators enables.

Just reported because it seems weird and can help others.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2025-05-01 13:38:02 +0200 (Thu, 01 May 2025)
Revision:19396
Build-Date:2025-05-02 01:30:34
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (19396 en) Linux openSUSE Tumbleweed
Memory Usage: 376 MB / 7956 MB (139 MB allocated, but free)
Java version: 21.0.7+6-suse-1.1-x8664, N/A, OpenJDK 64-Bit Server VM
Look and Feel: javax.swing.plaf.metal.MetalLookAndFeel
Screen: :0.0 1366x768x[Multi depth]@60Hz (scaling 1.00×1.00) :0.1 1920x1080x[Multi depth]@[Unknown refresh rate] (scaling 1.00×1.00)
Maximum Screen Size: 1920×1080
Best cursor sizes: 16×16→16×16, 32×32→32×32
Environment variable LANG: C
System property file.encoding: UTF-8
System property sun.jnu.encoding: UTF-8
Locale info: en_US
Numbers with default locale: 1234567890 -> 1234567890
Desktop environment: KDE
Java package: java-21-openjdk:x86_64-21.0.7.0
apache-commons-logging: apache-commons-logging:noarch-1.3.4
VM arguments: [--add-exports=java.base/sun.security.action=ALL-UNNAMED, --add-exports=java.desktop/com.sun.imageio.plugins.jpeg=ALL-UNNAMED, --add-exports=java.desktop/com.sun.imageio.spi=ALL-UNNAMED, -Dsun.java2d.opengl=true]
Dataset consistency test: No problems found

Plugins:
+ FastDraw (36438)
+ ImportImagePlugin (36438)
+ ImproveWay (36)
+ Lanes (${version.entry.commit.revision})
+ RoadSigns (36438)
+ apache-commons (36438)
+ conflation (269)
+ contourmerge (v0.2.2)
+ ejml (36438)
+ geotools (36438)
+ jackson (36438)
+ jaxb (36438)
+ jts (36438)
+ opendata (36440)
+ reltoolbox (36438)
+ reverter (36438)
+ shrinkwrap (v1.1.3)
+ splinex (36438)
+ tageditor (36438)
+ turnlanes (36438)
+ turnlanes-tagging (1746100629)
+ turnrestrictions (36438)
+ undelete (36438)
+ utilsplugin2 (36438)
+ wikipedia (435)

Tagging presets:
+ https://josm.openstreetmap.de/josmfile?page=Presets/Healthcare&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Presets/LaneAttributes&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Presets/Wikidata&zip=1

Map paint styles:
- https://josm.openstreetmap.de/josmfile?page=Styles/Surface&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Surface-DataEntry&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Lane_features&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Lane_and_Road_Attributes&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/PublicTransport&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/PublicTransportV2&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Waterways&zip=1

[gaben]

When did you last use JOSM before the 'big update'?

Until this sentence it's normal nowadays due to high server load

When clicking in File-Download data i have to wait aprox 10 seconds before the Download window appears.

[anonymous]

I was using without any problems just before the 'big update'.

Now I'm always starting josm with option -Dsun.java2d.opengl=true because it starts faster. Then during editing elements the speed improvement, if any, is not noticeable by me.