410369 - Some operations are very slow on large numbers of messages

Status: RESOLVED FIXED

(MailNews Core :: Backend, defect)

Description

[[e-mail]]

While trying to clear out a mailbox with about 100000 messages I ran into the problem that almost everything I did was painstakingly slow. Often the problem was building up an array an element at a time so I checked nsMsgDBView.cpp to see where we could reserve space or otherwise avoid reallocating.

Comment 1

[[e-mail]]

Attachment: Some speedup

Most of the optimisation here is concerned with using SetSize and SetAt instead of Add, however for mark thread as read I just allocated the space as some of the thread may already be read, while for expanding a thread I preinserted the number of elements I thought I was going to add in advance; this is the trickiest part of the patch and if you prefer we can address that separately.

Comment 2

[David :Bienvenu]

Comment on attachment 294992 [details] [diff] [review]
Some speedup

thx, Neil - seems to work fine so far...

Comment 3

[[e-mail]]

Fix checked in.