David Bienvenu wrote:
> Seth Spitzer wrote:
>
>>
>> If you were to delete 20 messages from a folder with 1,000 we'd
>> unassert on every message we delete. This would cause us to reflow
>> and scroll 20 times, which is very expensive.
>>
>> My fix is to call beginBatch() when we call delete with more than <n>
>> messages, and then when the delete is complete, call endBatch().
>>
>> (<n> is not determined yet. we might have to think about computing it
>> based on the number of messages to delete and the number of messages
>> in the folder.)
>
>
> Awesome. One thing, though, I think the number of messages in the folder
> is not as important as the number of messages on screen, since it's the
> messages on screen that reflow. But I think <n> could be as small as 2
> or 3. We'll have to see.
more info:
When I use the tree batching API, here's a scenario where I see a big
performance win:
have folder with 1000 messages
scroll down to message 500
select messages 25
scroll down a little more so the selected messages are off screen
hit delete
If I don't use batching, after ever delete happens, we automatically
scroll up one line, and we have some repaint problems. (we've all seen
this.)
when I use batching, the automatic scrolling only happens when all the
deletes are complete.
When deleting doesn't cause scrolling, I don't think we suffer the same
performance problems.
-Seth
