https://bugs.kde.org/show_bug.cgi?id=338571
Tore Anderson <t...@fud.no> changed: What |Removed |Added ---------------------------------------------------------------------------- Resolution|WAITINGFORINFO |--- Status|NEEDSINFO |CONFIRMED --- Comment #52 from Tore Anderson <t...@fud.no> --- OK, I have now tested KMail 5.14.1/Akonadi 20.04 in a freshly installed VM running Fedora 33 Rawhide. Then I compared it to the behaviour of Thunderbird. tl;dr: * KMail/Akonadi spends ~63 minutes on opening a large IMAP folder (133k messages) that Thunderbird spends ~8 minutes on. 688% increase with KMail/Akonadi. * KMail/Akonadi generates an overall higher load average than Thunderbird does (even without taking into account that it does so for a much longer period of time) * KMail/Akonadi ends up requiring 1703 MiB of disk space, Thunderbird only 124 MiB. 1273% increase with KMail/Akonadi. So by every single observable metric, KMail/Akonadi is *extremely* inefficient and slow. In fact it manages to use more disk space than Thunderbird does in the end, even *before* any IMAP account has been created (cf. comment #49). That is just ridiculous. Here is the exact test procedure I used. I'm using the IETF public IMAP server, so anyone can try to do the same. 1. Launched KMail, dismissed the initial account setup wizard. 2. Settings -> KMail settings -> Receiving tab -> Add...custom account -> IMAP 3. General tab: * Account name: IETF * IMAP Server: imap.ietf.org * Username: anonymous * Password: anonym...@ietf.org * Uncheck download all messages for offline use * Uncheck regular checking of e-mail Advanced tab: * Encryption: none 4. Pressed OK, waited for folder list to be downloaded 5. Found the folder named just "ietf" in the list, clicked on it as I started a stopwatch (@11:40). This folder has about 133.000 messages in it. 6. Waited until folder sync and threading had completed After ~15 minutes: folder sync 22% completed, 15-min load average 0.52 After ~30 minutes: folder sync 47% completed, 15-min load average 0.88 After ~45 minutes: folder sync 73% completed, 15-min load average 1.39 After ~60 minutes: folder sync 100% completed, 15-min load average 1.63 At this point, KMail is still busy doing stuff. Status bar says «grouped X of Y threads», «processing X of Y messages», etc. After ~63 minutes: KMail finally idles. 15-min load average 1.61 7. Closed KMail 8. du -ms ~/.local/share/akonadi -> 1703 MiB I then compared with Thunderbird's behaviour: 9. Launched Thunderbird (version 68.8.0) 10. In inital account wizard: * E-mail address: anonym...@ietf.org * Password: anonymous Click "Manual settings": * Incoming server name: imap.ietf.org * Incoming SSL: none * Incoming authentication: regular password * Configured a random outgoing SMTP account (since it's required) * Clicked "Test Again" * Clicked "Advanced settings" * Server settings page: Unchecked "Look for new messages on startup" * Server settings page: Unchecked "Look for new messages every 10 minutes" * Synchronisation and storage page: Unchecked "Keep messages in all folder for this account on this computer" Press OK 11. In advanced config editor: set mail.server.default.using_subscription to false 12. Restart Thunderbird (apparently necessary for mail.server.default.using_subscription to take effect), let it load the list of shared folders 13. Clicked the "ietf" folder and started stopwatch Waiting until folder sync was done: After ~5m: 98k of 133k messages processed (~74%), 5-min load average 0.68 After ~8m: completed. 5-min load average 0.62 14: du -ms ~/.thunderbird -> 124 MiB Tore -- You are receiving this mail because: You are watching all bug changes.