158860 - Reduce memory cost of using HTML Source multiple times

Status: RESOLVED FIXED

(SeaMonkey :: Composer, defect)

Description

[Charles Manske]

Each time we switch from "Normal" editing mode to "HTML Source" and make any 
change, when we switch back to "Normal" we reparse and rebuild the entire 
document. The transaction system caches *all* DOM nodes because of this. With the
current unlimited under model, this can cause large amounts of memory to be used
after repeated uses of HTML Source mode.
We can limit this to just one document tree in the cache by limiting the undo
stack to just one when going from HTML Source mode to Normal mode.

Comment 1

[Charles Manske]

Attachment: patch v1

Comment 2

[Charles Manske]

To test:
1. Do some editing in Composer page. Type some, insert an image, insert an HR.
2. Use Undo to see that all of the editing tasks can be undone, using Undo multiple
times.
3. Click on "HTML Source" tab and make some changes to the source
4. Return to "Normal Mode"
5. You can use "Undo" once -- it should undo all the changes you made in HTML 
Source.
6. After using Undo once, Undo is disabled and you cannot undo any of he actions
previous to the HTML Source changes.

Comment 3

[kinmoz]

Comment on attachment 92394 [details] [diff] [review]
patch v1

sr=[e-mail]

Shouldn't the max transaction count used be 1 instead of 2?

Comment 4

[Charles Manske]

Note: Setting the maxTransaction count to 1 is what I tested:
+ gEditor.transactionManager.maxTransactionCount = 1
so that's what I'll checkin.

Comment 5

[Kathleen :Brade]

Comment on attachment 92394 [details] [diff] [review]
patch v1

r=brade

Comment 6

[Asa Dotzler [:asa]]

Comment on attachment 92394 [details] [diff] [review]
patch v1

a=asa (on behalf of drivers) for checkin to 1.1

Comment 7

[Charles Manske]

fixed in trunk

Comment 8

[Dimitrios]

Assuming I have understood the purpose of this bug, a similar practice is
followed by MS Frontpage, too. I was wondering why, until I saw the reason here.
But I think it should be mentioned in 1.1 release notes.