Daniel Dekany wrote: > If I edit a not small document (1M DocBook) and the on-the-fly spell > checker is on, it causes annoying slowdown (CPU: AMD XP 1600+) when I > press arrow-down to scroll. It will continue scrolling after releasing > the the key (like for 1 seconds for a typical scrolling, but more if I > wanted to scroll more) because it can't keep up with the repletion > rate of the keyboard. Without on-the-fly spell checker no such > annoying slowdown is perceivable. Now, you may say my CPU is old, etc, > but let me do two notes: > > - It appears to me that the rate of this slowdown depends on the size > of the document. Like with a 74K DocBook (which is still several > "pages") I don't perceive any slowdown. Is it really necessary that > this continually perceivable resource consumption of a spell checking > grows as the document grows (after it has reached a certain size, of > course)? I don't see any such theoretical necessity. > > - I have edited documents of similar size with MS Word on much slower > computers, and while the spellchecker may be delaying sometimes > (especially right after opening the doc), it didn't slowed navigation > down. It was like running in parallel with everything else. > > So, maybe some architectural redesign could fix these. >
> And the same problem occurs even if I just move left or right with the > caret inside the *same* line. If the on-the-fly spell checking is off, > moving the caret continually within the same line causes like 5% CPU > usage (with rare spikes of 30%). But if I turn on-the-fly spell > checking on, moving the cursor on the same way will *continually* eat > 100% CPU time, i.e. the CPU can't keep pace, so the caret movement > will be slower and it will continue movement after releasing the arrow > key. Quite inconvenient, but most importantly, quite strange; why is > it so CPU intensive to move the cursor? I don't even modify the line > or cause new lines to show, so what is it working on so hard? Must be > a bug. The above bug is fixed. Bug fix available in next release. This bug fix has also improved the scrolling performance of XXE when you keep the Down Arrow pressed. However, XXE is still slower when on-the-fly spell checking is turned on than it is when this facility is turned off. (I've done all my tests using a 2.2Mb DocBook document opened in XXE running on a P4 1.7GHz, 768Mb, no graphics card, Windows XP SP2, Java 1.4.2.)
