[PATCH] Significantly reduce freeze when deleting a node with the relation editor open

[taylor.smock]

From comment:36:ticket:21825 (test relation was ​Lake Huron):

Measurements (async profiler) for attachment:21825.avoid_loop_MemberTableModel_wayNodesChanged.patch:ticket:21825​

Original code (no patches, jar downloaded from website, 30s for update on node delete, profiling was ~36s long, EDT blocked for ~30s):

• CPU
  • EDT: 69.31% of all
    • MemberTableModel#wayNodesChanged: 65.89% of all, 95% of EDT
  • G1: 21.09% of all
• Memory
  • EDT: 80.75% of all
    • MemberTableModel#wayNodesChanged: 66.93% of all, 82% of EDT
    • MapView painting: 13.07% of all, 16.18% of EDT
  • AutoSaveTask: 19.16% of all

New code (~6s for update on node delete -- most of time is from moving mouse to start/stop profiling, also has validator changes, EDT blocked for <1s at any time):

• CPU
  • EDT: 16.99% of all
    • MemberTableModel#wayNodesChanged: 1.98% of all, 11.65% of EDT
  • G1: 6.31% of all
  • Validation: 68.41% of all
• Memory
  • EDT: 97.76% of all
    • MemberTableModel#wayNodesChanged: 6.04% of all, 6.17% of EDT
    • MapView painting: 79.59% of all, 81.41% of EDT
  • Validation: 1.48% of all

No listeners (at least in core JOSM) actually check for which column is modified. Or even what changed in the table.

[taylor.smock]

Standalone patch: Avoid loop in MemberTableModel#wayNodesChanged. This decreases UI freeze from ~20s to <1s for ​Lake Huron. (Same as attachment:21825.avoid_loop_MemberTableModel_wayNodesChanged.patch:ticket:21825​ )

[stoecker]

Why don't you simply apply it?

[taylor.smock]

Replying to stoecker:

Why don't you simply apply it?

Short answer: It takes me some time to get svn up and running on my work computer (I have to use svn in a docker container), and I was out of work time for the week.
And then I had some different work to do. Which I just finished.

I'll be pulling it down on my home computer now that I've got a minute.

[taylor.smock]

In 18401/josm:

fix #21950: Significantly reduce freeze when deleting a node with the relation editor open

This specifically affected large relations, like that for Lake Huron (relation
1205151, ~14.5k members). This specifically reduced the UI freeze time when
deleting a node that is part of a way in the relation when the relation editor
is open from ~30s to <1s.