Performance

[mamacdon]

Figure out why CodeMirror is so much faster at responding to significant damage in the editor.

Potential problem areas:

Too many styling passes:
To avoid hanging the UI, the styler does 50ms or 800 lines' worth of styling, then pauses for 75ms. This is too conservative; it takes a long time to finish a large file.

Generating too much garbage:
Profiling shows anywhere from 13–30% time spent in GC. Some of this is due to plugin-communication overhead, but I may be allocating too much crap while parsing or something.

Data structures:
When styling a line of code like this:

var fizzbuzz;

CodeMirror internally represents the line's style as an array of alternating token and text-fragment:

[ "keyword", "var", null, " ", "variable", "fizzbuzz" ]

The Orion-codemirror highlighter instead stores a range of token+line indices, and no text:

[ [0, 3, "keyword"], [4, 12, "variable"] ]

Perhaps the extra level of arrays here is increasing pressure on the VM and making it slower???

[mamacdon]

Moved over to Bugzilla since nobody pays attention to the Issues on here

https://bugs.eclipse.org/bugs/show_bug.cgi?id=365128