KMail: slow path that causes threading to take forever
Closed, WontfixPublic


Sometimes we hit a slow path in kmail threading, where it kmail can max out a cpu for serval minutes to thread just a couple of thousand mails.

All time, according to sysprof, is spent in this codepath:

QAbstractItemModelPrivate::rowsAboutToBeRemoved(QModelIndex const&, int, int)                                                                            7.31%  73.98%
   MessageList::Core::Model::parent(QModelIndex const&) const                                                                                             5.81%  64.26%
     MessageList::Core::Model::index(MessageList::Core::Item*, int) const                                                                                 6.15%  52.34%
       MessageList::Core::Item::indexOfChildItem(MessageList::Core::Item*) const                                                                         17.49%  37.77%
         QList<MessageList::Core::Item*>::count() const                                                                                                   1.61%  14.72%
         QList<MessageList::Core::Item*>::at(int) const                                                                                                   1.47%   3.70%

This is likely an explosion of signals in the model stack, and not the threading code itself


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mollekopf updated the task description. (Show Details)
mollekopf raised the priority of this task from to 60.
mollekopf added a project: KDE PIM.
mollekopf changed Ticket Type from Task to Task.
mollekopf added a subscriber: mollekopf.

First we need to figure out why we have so many rowsAboutToBeRemoved signals, if we indeed require that many, MessageList::Core::Model::index likely needs to be improved.

It's rather likely that we have too many signals in the first place though (we already know this for other signals, but failed to fix this properly so far).

mollekopf moved this task from Backlog to Workaround exists on the KDE PIM board.May 14 2015, 2:18 PM
vanmeeuwen lowered the priority of this task from 60 to Normal.Mar 28 2019, 8:13 AM
machniak closed this task as Wontfix.Jul 16 2019, 11:45 AM
machniak claimed this task.
machniak added a subscriber: machniak.

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