User Agent: Mozilla/5.0 (Windows NT 6.1; rv:10.0.2) Gecko/20100101 Firefox/10.0.2 Build ID: 20120215223356 Steps to reproduce: When using Thundbird (10.0.2) with Lightning enabled, writing an email is annoying in that there are frequent, long (5 seconds) pauses before typed characters appear. With Lightning is disabled the problem disappears. Actual results: It appears that Lightning is consuming a lot of processing power or it has delays in it. Perhaps it is searching a database too thoroughly and too frequently. Expected results: Since Lightning is a background application to Thunderbird, it should not be such a consumer of resources. I have this problem in two computers, a Dell running 32-bit Windows 7 and an HP running 64-bit Windows 7.

(In reply to krt2076 from comment #0) > When using Thundbird (10.0.2) with Lightning enabled, writing an email is > annoying in that there are frequent, long (5 seconds) pauses before typed > characters appear. With Lightning is disabled the problem disappears. krt, fIf lightning is the only thing you disabled ... does your issue match one of these other bugs? https://bugzilla.mozilla.org/buglist.cgi?type1-0-0=substring;keywords=perf;keywords_type=allwords;list_id=2845058;field0-0-0=short_desc;type0-0-1=substring;field0-0-1=keywords;type1-0-1=allwordssubstr;resolution=---;classification=Client%20Software;classification=Components;query_format=advanced;type0-0-0=anywordssubstr;field1-0-0=short_desc;product=Calendar;field1-0-1=short_desc

I looked through the other bug reports and did not find any that appeared to match my report. What I am describing happens on two machines, an HP 64-bit running Windows 7 Ultimate and a Dell 32-bit running Windows 7 Enterprise. Disabling Lightning has the same impact, viz., there are no pauses when typing in Thunderbird. Even when Lightning is engaged the pausing does not always appear, but does happen more than half the time at some point in the preparation of an email, having just happened while typing this. FWIW, starting Thunderbird with Lightning enabled takes considerably longer then when Lightning is disabled.

Hi, I can confirm that TB slow down if Lightning is actic. TB stopps working for about 3 seconds frequently (appr. every 30 seconds) A change to the calendar tab needs takes about 5-7 sec. to show calendar entries. I'm using Win XP SP3 German, TB 14.0, Lightning 1.6, with a small Netbook. Before version 1.3?, the installation worked without -unnormal- delays. On another PC, WIN 7 (64 bit), the slowdown is noticeable also. But not so annoying... Ralf

Same problem here. Unbearably slow under Windows.

Still a problem with this "minute's of silents" here (TB 16.0.1, Lightning 1.8 under Win XP sp3, home, german, 32bit and WIN 7 prof, german 64bit). During the break, within the status bar (below at the window, a kind of progress bar is shown. But it is not showing a progress... Then the window (calendar view) will be refreched. Additionally it seems that Lightning is handling all defined calendars even if they are not selected. I guess it is time to change the bug-report to status confirmed!? Who can do that? Gruss Ralf

Same problem here: * delays in writing emails * thunderbird stop responding for long periods (just now killed it with Task Manager) More info: * windows 7, 64 bits * thunderbird beta channel 17 (32 bit) * ligthning 1.9b2 * Provider for google calendar 0.18pre On point that I think is relevant is that I'm only using calendars from google calendar. The delay may be related to access to google. In Linux however (with the same calendars but the stable version of thunderbird 16 and lightning 1.8) this does not seem to happen. Best, Pedro

Within the past 2 1/2 weeks, Thunderbird has slowed down I N C R E D I B L Y for us. Some/many are using Google calendar.

(update to comment 4) have a lookc at https://bugzilla.mozilla.org/buglist.cgi?type1-0-0=substring;keywords=perf;keywords_type=allwords;list_id=4853331;field0-0-0=short_desc;type0-0-1=substring;field0-0-1=keywords;type1-0-1=allwordssubstr;resolution=---;resolution=FIXED;resolution=INVALID;classification=Client%20Software;classification=Components;chfieldto=Now;query_format=advanced;chfieldfrom=2011-01-01;type0-0-0=anywordssubstr;field1-0-0=short_desc;product=Calendar;field1-0-1=short_desc

I recently moved a customer over to Google Apps for Business with Thunderbird. After adding Lightning, they started complaining about the speed. We disabled Lightning (literally, the disable button) and the speed issues were resolved. Of course, they need their calendar. So, we enabled the 30 day premier trial, and added the Google Apps sync for Outlook to their computers, and all is well. This stinks. I want to advocate for open source, but this makes Thunderbird an unbearable replacement for Outlook. I know Thunderbird on its own isn't meant to compete directly, but I wish there was a really good replacement for Outlook on Windows.

Same problem as pbrandao: As of a couple months ago, Thunderbird+Lightning has become very slow to start and stalls often. Not sure which version it started, but I'm now on latest TB 17.0, Lightning 1.9 and Provider for Google Calendar 0.18 At startup, Thunderbird hangs for minutes before operating normally. Thereafter, Thunderbird will periodically hang again for awhile. I'm on Win7-64bit. The problem is specifically the google calendar support. If I delete my google calendar subscription, it resolves it. As soon as I add the google calendar subscription again, it's back to massive stalls. If I disable Lighting entirely, it's obviously resolved.

I'm having this same issue, it's gotten way slower in the past few weeks/months. It was really bad a couple years ago, I started looking into it, and it improved, so I quit, and now it's back. Typing an email is now excruciating. Lighting 1.9, Google Provider 0.18, 5 calendars I may try to hack it to only talk to the network on manual refresh, not sure if that'll be possible, or if it'll help. Chris

Yep, me too. Thunderbird became very slow recently. I have 3 POP mail account & 2 IMAP Thunderbird 17, Lightning 1.9 Google Provider 0.18, just one calendar.

Wonder if this is connected to Bug 818448 ?

(In reply to Gene Scharmann from comment #13) > Wonder if this is connected to Bug 818448 ? I experience the same slowliness but don't witness any increase in explorer.exe memory usage (Win 7 64 bits, TB 17, lightning 1.9, but no Google Provider) Enabling or disabling the lightning extension is enough to switch from a TB startup time of a few seconds to a few minutes, which is completely unbearable. On the other hand my linux box, which runs a similar setup, does not have any problem. Perhaps is it a windows-only bug ? I'll try to get a log of what's going on but I fail to see what module should be logged...

This bug is still here on Thunderbird 19 and Lightning 2.1b1

I have repeatedly noticed this problem on various linux installations and instead used sunbird which did not have any problems. Since the update to opensuse 12.3, sunbird is not functional for me anymore and I therefore have to use lightning. The reduction of responsiveness is very noticable on my machine, and I would enormously appreciate if a solution could be found.

Same problem in Windows. To get the calendar working I searched a very old version of Thunderbird 9.0.1 + Lightning 1.1.1 : it works perfectly, but this is not a solution! Status of this bug is still "unconfirmed" after 1 year from the first report... so nobody will take care of this, I guess..

(In reply to marco from comment #17) > Same problem in Windows. > To get the calendar working I searched a very old version of Thunderbird > 9.0.1 + Lightning 1.1.1 : it works perfectly, but this is not a solution! Not a solution, but a hint. Somewhere between then and now (or first report of the bug), it broke. If you can work with some people on in between versions, it might be further narrowed down and identified. This is why it is nice having a large base of "testers" looking at these programs. Without "testers", developers would have no feedback on the product.

I can only confirm this bug. TB 17.0.5 + lightning 1.9.1 + Provider Google Calendar 0.18 Writing a new messages it's a pain ! Also changing the preview pane from a messages to another it's really slow. I dont' remember when exactly this started but i think in the last six months or the last year so this is compatible with the first messages of this thread.

Still like it in Windows TB 17.0.8 with Calendar on Communigate Pro and/or Google. Problem goes away if you disable Lightning add-on. OS X suffered same problem too, so I disbanded Lightning in favour of iCAL and TB mail recovered its performance.

Does it help if we offer money, and if so, how much?

This has appeared again recently.

Similar here with thunderbird-17.0.9-1.fc19.x86_64 on Fedora Linux . Mail typing slowing from time to time plus when looking at calendar, it sometimes is "blinking": items disappearing and then reappearing in around half a second.

I'm experiencing this as well as described above (TB 24.0.1 w/ lightning 2.6). Latest TB/Lightning version have not changed anything. The delay / duration of the lag seems to be proportional to the number of calenders (or calendar events downloaded?). TB takes 1 full core of the CPUs during this. Any way we/I can help with a trace or logfile ?

Same problem after the Thunderbird update to 24.0.1 - typing slows down, stops , starts at random- tired running with no addons - worked OK- restarted- worked Ok for a few minutes then boom - back down to superbly slow and making my life miserable. I switch back and forth between Word7 and Thunderbird cutting and pasting- then seems to lose US keyboard and some characters get changed to other language, Thunderbird freezes up and have to hard reset and CTL, ALT Del does nothing - Checked everything else out. Disabled Virus protection, firewall, etc etc watching progress with Process Explorer to see if anything else is interfering - Not using anything in my Calendar to keep it simple- but still causing massive headaches! Also using Noia exTreme 3.47 and when moving to Word 7 from Thunderbird - see cursors changes and blink -

With the new update to TB 25.0 and Lightning 2.7, TB completely freezes upon starting if lighting is enabled. Old Lightning versions do not work at all with TB 25.0. In any case, since TB17 I have not found anymore a working Lighting version that does not slows down TB in an unacceptable fashion. Not usable anymore :-(( I had some hope in TB 25.0 and Lightning 2.7, but ithas been already frustrated:-(

Same hers...Bug was open March 2012-more than 18 months ago and noone from Mozilla even looked at that??? That seems strange or lack of interest by Mozilla to what its users has to say...

That's not a solution, but here helped to remove lightning and Thunderbird, then installing TB 9.0.1 with lightning 1.1.1 Obviously, you have to disable "check for updates" in Tool/option menù. "once upon a time there was an app... working"

If the Offline Support option for network calendars is disabled, enabling it should improve performance. Right-click on each calendar in the calendars list on the left side of the window, click Properties, and make sure the Offline Support option is checked. If the calendar is not shared with other users you can also set the Refresh interval to manual, that will prevent the calendars from re-loading periodically in the background.

Matthew, that didn't help. I have 5 calendars on th list, but enabled only one. On that calendar I have Cache enabled and Refresh interval to manual. Still the startup time is about 60-70 sec.

Even if I disable all calendars, the startup is slow. If I disable the Lightning plug-in. Startup is normal.

(In reply to peshko.us from comment #31) > Even if I disable all calendars, the startup is slow. If I disable the > Lightning plug-in. Startup is normal. When you say the calendars are disabled, are they just unchecked in the calendars list, or are they fully switched off from the calendar properties dialog? The checkbox in the calendar list will only prevent the calendar from being displayed in the view, but it will still load at startup, display reminders, and refresh. To completely disable the calendar you need to right-click the calendar in the list, click Properties, and uncheck the "Switch this calendar on" checkbox. A completely disabled calendar will show as greyed out in the calendar list.

CONFIRMing, because the summary statement is definitely true, I've experienced it myself. Part of the problem seems to be that Lightning creates a lot of JS objects that put the JS engine under great stress. Other problems like bug 841995 (see blockers here) contribute, too.

(In reply to Matthew Mecca [:mmecca] from comment #32) > (In reply to peshko.us from comment #31) > > Even if I disable all calendars, the startup is slow. If I disable the > > Lightning plug-in. Startup is normal. > > When you say the calendars are disabled, are they just unchecked in the > calendars list, or are they fully switched off from the calendar properties > dialog? The checkbox in the calendar list will only prevent the calendar > from being displayed in the view, but it will still load at startup, display > reminders, and refresh. To completely disable the calendar you need to > right-click the calendar in the list, click Properties, and uncheck the > "Switch this calendar on" checkbox. A completely disabled calendar will show > as greyed out in the calendar list. Correct, all but one disabled in the properties. All but one grayed out in the list. Still startup time over a minute.

Hi, FYI, I am also affected by issues described in this ticket. It was occurring with TH14+Lighting1.9.1 and it is still occurring in my current environment after upgrade: - Win7 Pro 64bits SP1, Intel Core i3-2310M 2.10GHz, 4GB memory - Thunderbird 24.2.0 - Lightning add-on 2.6.4 - Two mailboxes connected via IMAP (one of them almost empty) With Lightning add-on disabled (and all other as well) it takes: - ~5s for Thunderbird interface to first show up from clicking on icon to open it - ~20s additional to complete any activity in status bar (check new email, folders, etc...) Total: ~25s With Lightning add-on enabled but all calendar disabled (in properties) and greyed out - ~25s for Thunderbird interface to first show up from clicking on icon to open it - ~20s additional to complete any activity in status bar (check new email, folders, etc...) Total: ~45s With Lightning add-on enabled, one Internet Caldav calendar enabled (in properties) with show reminder enabled, offline support disabled and all others greyed out - ~12s for Thunderbird interface to first show up from clicking on icon to open it - ~78s additional to complete any activity in status bar (Check server capabilities, Looking for folders, etc...) and complete loading of the calendar. During this time, the interface responsiveness is very poor and slow with (Not responding) warning appearing intermittently every 4-5s after 40s until completion of process. Obviously both process of Checking email and loading Calendar run at the same time at start-up and seems to overload the application to the point it become unresponsive... it looks like concurrent processes are not running smoothly in parallel... Total: ~90s Hope this info may help. Thanks for your support.

Sorry I meant TH17+Lighting1.9.1 in my previous comment...

On my system (WinXP SP3, TB 24.2.0, Lightning 2.6.4) this performance issue seems to be due to extensive disk activity in my profile's calendar-data directory. All this disk I/O seems to make Thunderbird crawl, as well as adversely affecting other applications.

I just did a test installation with TB 24.3.0 & Lg 2.6.4. (Win7) I have 10 network calendars active (Google, caldav) and TB takes about 3+ MINUTES (!) to start. This is my daily struggle (except when i start with all add-ons disabled, of course, as others have reported) For testing purposes I removed the calendar-data\cache.sqlite file and started TB again with all add-ons active. It was there in a jiffy (5 secs or so) and slowly re-loaded the calendar entries from the network. bug no lag or startup delay. to me this reads that it HAS to do with cache synchronization during startup... right?

The same for me. We use TB + Lightning in a team. And the current behaviour is really annoyning and makes TB nearly unuseable. I am not sure but I guess the situation became worse since the last update. Currently I am running: * TB 24.3.0 * Lightning 2.6.4 * Provider for Google Calendar xx * 4 network calendars (Google, caldav) OS: Win 7 , X64 This problem is urgent and makes TB unuseable. Click > 10 seconds > Click > 10 seconds. After deactivation of Lightning everything runs fast.

> After deactivation of Lightning everything runs fast. Note that the problem gets worse over time, so a restart alone can improve things temporarily. That said, Lightning does make the situation considerably worse. This issue needs urgent attention from the Lightning owners. Tip: Separate Lightning into its own process, by creating a second Thunderbird process, starting it with thunderbird.exe -new-instance -P <profilename>, and installing Lighting there, and ignoring the mail part, effectively creating a "Sunbird".

So I observed the following after yesterdays test: after cleaning (=moving) the cache.sqlite and having TB/Lightning re-populate it from the net, it was only 5MB as opposed to 21MB prior to that. TB 24 with Lightning 2.6.4 continues to start within a couple of seconds. could it be that carbage is piling up in the .sqlite db/file ?

Confirming the slow-down on Fedora 20. I noticed it today when I switched over to using CalDAV to access google calendars. Every so often, presumably when refreshing these calendars, Thunderbird becomes very busy and impossible to use.

This performance problem has been around for ages. It is probably the only thing that could force me to go back to using Outlook, but it's getting worse,not better, and I am on the beta channel! Sorry I can't contribute to the code right now, but this is probably the single most important thing to fix across both Thunderbird and Lightning because it makes the product close to unusable. I have had 100% cpu utilisation for ages (20+ minutes) on a high spec i7 and it's all in TB and Lightning - and there is nothing to do!

Perhaps if Bug 401779 - Integrate Lightning Into Thunderbird by Default and Ship Thunderbird with Lightning Enabled were actually implemented, these slowness issues would be greatly reduced.

(In reply to Worcester12345 from comment #44) > Perhaps if Bug 401779 - Integrate Lightning Into Thunderbird by Default and > Ship Thunderbird with Lightning Enabled were actually implemented, these > slowness issues would be greatly reduced. there are no performance related "handshaking" issues between TB and calendar afaik. nor does Lightning being an addon that makes it significantly slower. So on what basis do you make this claim?

Worcester12345 has made this request on many unrelated bugs and has been warned many times that this is unproductive and violates etiquette. He knows the reasons why its currently not an option and I suggest to not further respond to his comment.

Hi Phillip, When you say '...he knows the reasons why it is currently not an option...' would you mind to add a link to referenced ressouces so other people linked to this ticket that are not aware of them could be made aware? While I agree with you that nagging on unrelated toppings to the bug is counter productive, I must admit that I agree with Worcester12345 in some way. From a business (and my experience) point of view, Thunderbird is the best suited to replace Outlook but its incapacity to manage Contacts, Calendars, Tasks by default in a modern and performant way make the switch over and management difficult if not a pain in certain circumpstances, aggravated with very high quantity of data to handle. For info there is already a plan in place to re-design Addressbook feature from ground up to address some of Contacts issues. Now to come back to this bug issue, would it possible to provide guidance on how end-users encountering issue could provide better feedback (error/bug/performance) as to help identify what is causing it as a step forward toward a solution? I believe that Thunderbird become unresponsive due to tasks taking too long to complete during which UI is 'frozen' (not respinsive) maybe due to two many concurrency (disk I/O issue, db concurrent locking, slow server answer over network when processing remote data, etc) or else. At this point we still don't know what is causing issue. When Thunderbird start it may be processing too much at the same time check email, load multiple calendars, refresh reminders, update synched contacts, check for updates, etc... all done in the same process (no parallell tasking, no tasks delayed) with UI becoming unresponsive until tasks are completed. I also noticed that sometime UI freeze suddenly and I don't now why until the reminder windows slowly pops up and slowly list reminders... after which UI is available again. It could also be the way network request are processed... failure or time out could trigger repetitive requests that finally succeed but reducing performance. This just a thought... Not a fact. Thank you for your assistance.

Helpful comments from Richard. What I can add is that when Lightning is referencing external calendars it can consume huge amounts of CPU for no apparent reason, removing these references certainly seems to reduce this behaviour. Startup is still very slow though. I have a "clean" Thunderbird running under W8 with no Lightning and it starts in about 20 seconds. A similar one under XP (which I have been using for ages) takes 2-3 minutes to show the list of folders and several minutes more to show the first messages - and I can't do anything until then! So lets say a startup time of 5-8 minutes. Disabling Lightning reduces this to about 30-40 seconds. Frankly I would be totally happy if Lightning did nothing at all until TBird was up properly. Hardware: Intel i7 with 20Gb memory 2Tb of disk with plenty spare, so it's not a hardware problem!

I am running Win7 Intel i& with 16 GB ram, 240GB SSD and then 2 TB data drive. After changing keyboard and mouse from wireless back to wired - TB 24.3.0 Lightning 2.6.4 plus 14 other add-ons, 6 different email addresses etc and years of history with over 500 folders - TB loads in 5 seconds Tried everything to get it working before and was superbly slow and blowing up all the time. This happened just before Christmas 2013 and after trying everything I could possibly think off- I changed a wired mouse and what a difference- so I bought new wired stuff- and everything is working really well to date!

travist, I'm delighted, but I have a real problem with your post. I have done a lot of timings on TB. 5 seconds is faster than a completely clean TB with no accounts can load on a machine at least as powerful as yours. OK the SSD could make a difference, but not to the level you are suggesting. In any even I have no wireless anything so that is clearly not the problem.

@travist Emails are not the issue. How many caldav remote calendars do you have set up? SSD would necessarily improve performance over traditional HDD. If disk I/O issue may be the reason SDD speed increase could compensate. I plan to migrate to SSD at some point I'll see if it make a difference. Definitely not wireless keyboard/mouse issue I use a laptop toshiba portege r830-139. Problem with (or over use of disk), memory, cpu are not to be excluded.

Hi folks, you can read a bit about it in bug 401779. The short version is that there are still to many issues in Lightning that would negatively affect Thunderbird's stability and performance. Then there will be various issues to take care of during integration, for example the massive amount of new localized strings that Thunderbird localizers will have to take care of. There are far more localizations for Thunderbird than there are for Lightning. Also, we don't have enough contributors to guarantee regular regression fixes and strong module ownership. The performance issue is not a new one, I am mostly aware what needs to be done to fix the issues. The problem is that the technical steps to do it are not trivial. Here is a short and incomplete list: * Rewrite the storage provider to use asynchronous SQL statements (bug 498968, bug 501689) * Rewrite parts of the calendar views to use more efficient data structures and less redraws (bug 924865) * Switch most providers to enable offline support by default (bug 462277) * Make some other processing parts asynchronous or have them use web workers (no specific bug) * Switch to ical.js so we can remove some abstraction that is causing slowdowns (bug 978570, bug 685884) * Move occurrence generation into a worker, These bugs alone could well cost a few full time developers multiple months of work. We don't have those kinds of resources. Aside from that, there are also short term bugs that need to be taken care of, i.e regressions due to platform changes, or the unloved improving unit test coverage, which is again a requirement to make such large changes as above. The issue is definitely not network performance, unless you have a lot of events and "Offline Support" is disabled. I don't think its a disk I/O problem, especially since we have WAL enabled (bug 918175). The biggest issue will be all the synchronous code that is blocking the UI. All the nice new asynchronous features were not there from the beginning and lots of things weren't refactored when they were made available. Back in/before Lightning 1.0, there were no web workers, no Task.jsm/Promise.jsm and the asynchronous SQL api also hasn't been there forever. Now I'd love to give you an action plan what you can do to help, but unless you are able to tackle any of the above issues, there is nothing I can say that I think will be satisfying for you. Of course, we need every hand we can get (even non-developers). The more independent you can work, the better. If you are good at writing blog articles and can keep an eye on what is going on at the calendar project, thats something that could save a little of my time, as well as keep people informed. If you've been reading a little on bugzilla you can also see that for most of the UNCONFIRMED bugs there are really but a few canned responses that need to be given to figure out if its a real issue (NEW) or just a support issue that needs a few comforting words (WORKSFORME). Doing that doesn't require you to read code, just being able to understand technical terms and reading a few logs is enough. What else do we need? Developers, UI Designers, beta testers, developers. I hope this clarifies some of the performance issues and gives you a better picture whats missing for great Lightning performance, and in turn for making Lightning an integrated part of Thunderbird.

Actually that turned out to be the long version :)

> The issue is definitely not network performance, unless you have a lot of > events and "Offline Support" is disabled. I don't think its a disk I/O > problem, especially since we have WAL enabled (bug 918175). ... WAL is only enabled in Lightning 2.9 and newer. If you are using network calendars and if you have enabled the "Offline Support" feature you could test Thunderbird 27 Beta + Lightning 2.9 Beta (or Thunderbird 28 Beta + Lightning 3.0 Beta) for improved performance. WAL should fix the problem as reported in e.g. Bug 841508. In addition you can try to reduce the work that has to be done by Lightning. For example switch the filter in the Find Events bar from "All" to something limited like "Current Month". This should reduce the number of calendars items that must be downloaded and processed by Lightning. Same applies for the task filter in Today Pane and task filter in Tasks Tab.

Everybody: Integrating Calendar into Thunderbird will only make this problem worse. Right now, the only workaround is to separate Thunderbird and Lightning and run them in different profiles. That makes the problem barely tolerable, even if still really disruptive for work. With both in the same profile, Thunderbird was entirely, completely unusable. So, any argument "Lightning should be integrated into Thunderbird" is totally wrongheaded here. In fact, this bug MUST be fixed BEFORE we can even consider such a move, or we will kill our userbase by making Thunderbird unusable. Please stop discussing this topic here, because it's completely offtopic here. Remember the bugzilla etiquette. <http://bugzilla.mozilla.org/page.cgi?id=etiquette.html>

Thank you all for your time, feedback and good work. @Phillip Thanks for the long detailed clear post. It does help to get to understand the current issue and state of play/path toward possible solution. Sad to hear that you lack ressources to tackle those long pending and complex bugs. For the moment I have other projects at hand but I'll see in the future if I can provide any help to have performance related issues sorted. @Stefan Thanks for the tips, I'll give it a try. Though I'll probably wait for stable version of TH 27/28 + LI 2.9/3.0 before trying as this is my work machine ;-) @Ben Thank you for the bugzilla etiquette reminder. I think here we all have in mind (at heart) to improve TH performance and expand userbase.

FYI, I enabled only three remote caldav calendar and activated calendar cache support on all but don't see much improvement. I don't have write-ahead logging (WAL) for cache.sqlite (Bug 918175) at the moment so disk I/O problem may not be excluded in my case, but that shall be sorted when 2.9 stable will be out ;-) Then it will be down to: "...The biggest issue will be all the synchronous code that is blocking the UI..." (from Phillip - Comment 52) ;-)

I've got 4 ICS calendars, all on file:/// URLs. And an Intel SSD. So neither network latency nor disk I/O are reason for the problem. I think the problem is excessive use of JS objects and too high pressure on the garbage collector.

I'm going to make a suggestion that may seem inelegant at the least, but it would help those of us who need to use this stuff day in day out, and it wouldn't be a big job. Can we have a load delay in Lightning, Ideally until TB is ready for action, but failing that, long enough to let TB get loaded for most users. I would suggest a minimum of 30 seconds perhaps longer. Secondly, when Lightning is loading/running, is it possible to pause and yield (not sure what the java is for this) regularly so that it doesn't block other activity. I realise this will make Lightning even slower but it should make TB faster and that for me would be a net win until we can get it fixed properly. At the moment I am contemplating moving my calendar exclusively to my S3 using Aquamail and SPlanner so that I can disable Lightning until it allows TB to be more performant - it's that important to me.

I am glad that now, after several years of waiting, this issue raises some broader attention. I have a feeling that all these unnecessary complications arise from the fact that someone decided to discontinue sunbird and insist on integration of the calendar function with thunderbird. I would be pleased if this could be just reversed: thunderbird as one functional entity and sunbird as another. Wouldn't that simplify everybody's life enormously? In my impression, sunbird was the only real functional calendar application in linux that made sense, and some time ago, the old version stopped to work for me.

Releasing a full application is a whole other can of worms. It requires much more attention than an extension. I would need to maintain our own build machines, (beta) releases need to be done every 6 weeks, extra QA, features need to be integrated into two different user interfaces, code needs to be written in a way that it works over two products, etc. Aside from that, Sunbird cannot handle email invitations, so users will still want something that handles this situation. Doing this across apps isn't possible unless you are using Thunderbird and we write some complicated code to interact with it when its running. Alas, if we were to continue to support Sunbird, then we would have to concentrate on releasing two products, and this is precisely what we wanted to avoid when we discontinued Sunbird. This issue has had the same level of attention in the last years, and with what I've explained this will not change just because a few comments were written here. I understand you all want to know whats going on, but this is not the right place to test theories of what would be better. This is the last comment I will write on this subject, please use the newsgroups (mozilla.dev.apps.calendar) for futher inquiries.

It sounds like this issue hast been around for quite a while now without a real solution. I have had it for 1 1/2 years now (with always the most recent version of TB and Lightning on Win7/64) - working with web interfaces instead of lightning and hoping for a solution with each new version of TB and Lightning - in vain. Reading all these posts here, it feels like the solution is still far away, and my technical knowledge is not large enough to really contribute anything to a solution (however: I can help if there are problems to reproduce the problem!). Therefore I am seriously thinking about the use of Thunderbird which also seems to have new small but annoying issues with every new version. It would be great to have some kind of a timeline for this issue. I really can't use Thunderbird like this, and I am thinking of switching back to Outlook - which would be a very sad transition, but I know no other really usable solution. My feeling ist: Wouldn't it make much more sense to really develop one stable version of Thunderbird instead of coming out with new versions every few weeks? I have the feeling that both Thunderbird and Firefox kind of degraded since Mozilla decided to increase the pace for new versions - and this persistence of such a serious problem is really sad. Sorry to say that.

This might not help, but I suddenly had this issue today out of the blue - I was prompted for my Google ID and Password, presumably to help synchronize my Gmail calendar with Thunderbird (not sure why it suddenly prompted, though) and then the 5-second pauses began. Made Thunderbird practically unusable. I managed to the Lightning extension, then restarted Thunderbird and all was fine. Then, something odd: I went into Thunderbird's "About" dialog and it tried to automatically update the program, but got stuck and never went beyond the "installing" message. My guess is that this was the case for months, as my version of TB was 26.x but the latest version turned out to be 31.1.2 when I manually checked on the Mozilla website. So, I downloaded the latest TB and installed over my current installation, then did likewise for the latest version of Lightning. Started TB and everything was working as expected, then installed the Provider for Google Calendar extension within TB and restarted. Integrated my Google Calendar back into Lightning via the new add-on (as opposed to using CalDev). UI performance is back to normal and my Google Calendar is properly integrated into the local Lightning view within Thunderbird. I realize this situation does not cover all issues mentioned within this bug, but hope it helps a bit.

I have this bug with Lightning 3.3.1 on Thunderbird 31.1.2. When writing new messages, Thunderbird hangs for 3-5 seconds, every 30 seconds. Uninstalling Lightning solves the problem. As I see this bug had been around since 2012, and it is not solved, this makes me seriously reconsider using Thunderbird. Since the price of Outlook has dropped significantly, I might just go back to Outlook altogether.

(In reply to bugzilla from comment #63) > This might not help, but I suddenly had this issue today out of the blue - I > was prompted for my Google ID and Password, presumably to help synchronize > my Gmail calendar with Thunderbird (not sure why it suddenly prompted, > though) and then the 5-second pauses began. Made Thunderbird practically > unusable. > > I managed to the Lightning extension, then restarted Thunderbird and all was > fine. > > Then, something odd: I went into Thunderbird's "About" dialog and it tried > to automatically update the program, but got stuck and never went beyond the > "installing" message. My guess is that this was the case for months, as my > version of TB was 26.x but the latest version turned out to be 31.1.2 when I > manually checked on the Mozilla website. > > So, I downloaded the latest TB and installed over my current installation, > then did likewise for the latest version of Lightning. Started TB and > everything was working as expected, then installed the Provider for Google > Calendar extension within TB and restarted. Integrated my Google Calendar > back into Lightning via the new add-on (as opposed to using CalDev). UI > performance is back to normal and my Google Calendar is properly integrated > into the local Lightning view within Thunderbird. > > I realize this situation does not cover all issues mentioned within this > bug, but hope it helps a bit. Thanks bugzilla@ooofest.com, that worked for me. :-) My Thunderbird was version 24.6 (not sure about the .6, sorry) with an older version of Lightning; perhaps I'd disabled auto update and forgotten about it. When I manually updated Thunderbird to the current version (31.1.2) and allowed it to find compatible versions of the addons, the problem (same symptoms, slow loading since a few days ago, when Google asked for my login details) and with the new Thunderbird and addons running, the problem seems to be gone. Hope your post brings relief to many other people. :-) (Windows 7 32 bit, Intel core2 duo, 4gb RAM, generic system with Gigabyte MB, Kaspersky Internet Security 2015.)

One potential workaround: I am using the same set of CalDAV calendars (with lots of events, tasks and alarms both single and recurrent ones) on a number of machines each with Thunderbird/Lightning (I love it). Surprisingly on my slower computers the sync and Thunderbird/Lightning were fast and the GUI smooth but on my fastest machine each start of Thunderbird and each (also periodic) sync of the calendars took forever (approx. 10min...). In addition the GUI blocked each time I made a change to something within any calendar. What resolved the slowness problem on the fast machine was simply (i) to unsubscribe from all my (CalDAV) calendars, (ii) to restart Thunderbird and (iii) adding the same calendars again by subscribing them in the same way as before. Clearly if your problems are due to intrinsically inefficient algorithms in Lightning and your machine is just to slow to process those in time then this workaround does not help you. By the way: Emptying the cache of the calendars (they are configured to have offline support) did not resolve my issue; only unsubscribing, restarting TB and subscribing again did.

Is anything in comment 63 deserving of a new bug report?

(In reply to Wayne Mery (:wsmwk) from comment #67) > Is anything in comment 63 deserving of a new bug report? I haven't looked to see if Thunderbird update bug reports exist, which would seem to be the most obvious issue that I encountered.

Lightning problems described in comment 63 might be caused by the broken Provider for Google Calendar 1.0 release or the access problems in the days after due to quota limit. Don't think any of this deserves a new bug report as they ought to be fixed now.

(In reply to Stefan Sitter from comment #69) > Lightning problems described in comment 63 might be caused by the broken > Provider for Google Calendar 1.0 release or the access problems in the days > after due to quota limit. Don't think any of this deserves a new bug report > as they ought to be fixed now. Not fixed yet.

For support issues regarding the Provider for Google Calendar extension please take a look at its support site <https://groups.google.com/forum/#!forum/provider-for-google-calendar>.

If you see slowness while using Thunderbird version 31, 38 or newer please post the URL from doing a profile while the problem is progress, per https://developer.mozilla.org/en-US/docs/Mozilla/Performance/Reporting_a_Thunderbird_Performance_Problem_with_G

Hi, I use Thunderbird 38.0.1 with Lightning 4.0.0.1. Every time I start Thunderbird, it starts running the CPU at 100% and for a minute I can't do anything with it. Occasionally it freezes much after start-up as well, but only if Lightning is enabled. With Gecko Profiler, I uploaded a dump file to http://people.mozilla.org/~bgirard/cleopatra/?1435411209547#report=436abe9ed418a2e2807f29f3c1a1f97faeed94ad which was made right after start-up. Is there anyone else experiencing this with the new Lightning? Can you reproduce the problem? Thank you for your help. Csaba

Hi Peter, thanks for uploading the profiler dump. The dump doesn't really show anything out of the ordinary, searching for alarms and loading the views are the items with most time spent in. If you are using the Provider for Google Calendar, please unsubscribe from the Birthday calendar. If you are using other calendars, can you let us know which? If you have a lot of old items that you no longer need, it would help to delete old items. I can understand this might not be wanted though. Also, if you have the event view set to "All Events", can you switch this to something else, e.g. events in the next 14 days?

Hi Philipp, thank you for the quick answer. I unsubscribed from the birthday calendar, and it fixed the problem indeed. Not long ago, I was still using Lightning 3, and I didn't experience any such problems with that. Will this be fixed at some point in the new version, or should I rather find an other way to get notified about the birthdays? Cheers

I will take a look at this in bug 1169062

Ralf reports ... issue is - nearly - gone for me. I assume this is depending on splitting big calendar in smaller ones. I'm also removing alarm-setting from past-events.solved his issues by splitting big calendar in smaller ones.

I can confirm that the single step of unsubscribing from the Birthday calendar brings startup time down from minutes (3-4!) to seconds. This has been a huge frustration for years! On the other hand, I would really like to have the Birthdays calendar...

We have here so many comments that are unanalyzed and in some cases "incomplete" that this has essentially become a mirror of the meta bug 441710, making this essentially an unactionable placeholder bug. We should await results of some of the bugs mentioned in comment 52 whose symptoms for some comments here a closer match than this bug summary, and also bug 441710, which includes bug 753343 which shares with this bug the symptom of jank/choppiness during compose. (But this bug lacks mention of high memory usage which is a prime symptoms of bug 753343. So hard to say if these share the same root cause - linking just in case.) Note also, the original reporter, krt, stopped using calendar couple years ago. So we won't be hearing from him. Volunteers welcome to assist Fallen and other developers in making patches.

Hi, I have the same problem on Fedora 22 Thunderbird 38.2.0

Its very slow and sometimes it craches

When I disable Lightning 4.0.2 it works fine

Please keep this bug for Lightning related problems. The hang in Thunderbird 38.2 is a known problem and is not related to Lightning. The cause for the Thunderbird problem is known and a fix is in work for 38.3, see Bug 1196662. I'd like to ask you to not add comments that don't provide new information.

(In reply to Ben Bucksch (:BenB) from comment #40) > > After deactivation of Lightning everything runs fast. > > Note that the problem gets worse over time, so a restart alone can improve > things temporarily. > That said, Lightning does make the situation considerably worse. > This issue needs urgent attention from the Lightning owners. > > Tip: Separate Lightning into its own process, by creating a second > Thunderbird process, starting it with thunderbird.exe -new-instance -P > <profilename>, and installing Lighting there, and ignoring the mail part, > effectively creating a "Sunbird". The combination of Thunderbird, Lightning and the Google Calendar Provider is very attractive, so it's a real pity that it is pretty much practically useless at present. This suggestion is not a bad compromise, hiding the underlying issues enough to make the platform usable. Here is what I did: 1. Create a new profile (eg Calendar) 2. Launch Thunderbird with --new-instance -P Calendar 3. Install Lightning, Google Calendar Provider, and Lightbird 4. Restart with --new-instance -P Calendar -calendar for a calendar only user experience

i confirm: disabling lightning (4.0.2) eliminates the problem. but with lightning enabled thunderbird is almost unusable. if it's so hard to find the problem maybe it would be a good idea to add some kind of profiles into the thunderbird. when user feels some problems, he turns on the profiler and call stack is being sampled. it should help find out which part consumes cpu

I don't know about others, but for me this problem has disappeared a long time ago. Comments to this thread seem to pop up with long intervals for some reason. I currently use thunderbird 38.3.0 on a linux machine, with lightning 4.0.3 and also lightbird 0.5, and everything is just fine.

I stumbled across Philipp Kewisch's comments: https://bugzilla.mozilla.org/show_bug.cgi?id=733039#c74 https://addons.mozilla.org/en-US/thunderbird/addon/provider-for-google-calendar/reviews/743276/ I followed the advice: "please unsubscribe from the Birthdays calendar" I unsubscribed from anything with "birthday" in its name, and I was very pleasantly surprised by the result. I have Thunderbird, Lightning and Google Calendar Provider in a single profile and about 9 calendars in play (definitely no birthday calendars of any kind) and the application remains usable and responsive.

I experiencing equivalent problems. I run Thunderbird 38.3.0 on Fedora 22. When Thunderbird runs longer than a day (and my Laptop is going into suspend für several hours in between, if that has any influence), it becomes very laggy too. I followed several suggestions on this page and some helped a bit. But the problem itself persists. The problem is getting worse, if you have some calendars, that are not accessible (due to DNS, VPN, WiFi or similar). The only chance to speed it up again is to quit and restart Thunderbird. If I restart Thunderbird, the file "<profile>/calendar-data/cache.sqlite-wal" will be removed and is recreated upon restart. After this, I can use Thunderbird for some hours without problems. I think the developers should investigate the behavior of Lightning, if it has problems to connect to the CalDav servers...

(In reply to quiet.dragon from comment #87) > I followed the advice: "please unsubscribe from the Birthdays calendar" I've been running with this configuration for about a week now. I start Thunderbird, and it stays running for days. On my desktop Ubuntu system, the Thunderbird+Lightning+Google Provider continues to function well. I have not had to restart Thunderbird since I deleted the birthday calendars. On my OSX laptop system, the performance started off well, but degraded slowly over the week with the occasional long delays in response to key strokes. The laptop is mobile moving from one WiFi system to another, but it's not possible to say if the intermittent connectivity is the root cause of the degradation.

Another datapoint: this problem only manifests on Windows. I run Thunderbird+Lightning on multiple Linux platforms with no problem, however on Windows, TBird+Lightning+Provider for Google Calendar = huge startup delays + frequent UI blocked for several seconds at a time. This suggests a blocking call to access the calendar API is taking place in the UI thread. A good workaround for windows users is the Google Calendar Tab add-on for Thunderbird.

On the other hand… I do experience this issue on Linux very much (on a quite recent machine with really enough CPU/RAM/IO bandwidth available). Further, the problem also occurs with subscribed calendars other than Google's (i.e. also w/o being subscribed to Google calendars but CalDAV ones etc.).

> this problem only manifests on Windows. Wrong. I see it on Linux, very strongly.

As an update to my previous post, the problem still persists under Linux (Fedora 23) using Thunderbird 38.6.0 (with Lightning 4.0.6) with several ical and CalDav calendars (to three different caldav servers). I disabled the ThunderBirthDay Addon, because it was almost unusable with it enabled. It works fine for several hours, but I have to restart it once a day to be usable (and responsive) again.

Is there some log or debug tool that Thunderbird has that we can look at? Since the issue only happens after hours of use it's really annoying to reproduce -- I assume this is why there hasn't been any progress in all this time P.S. Fedora 23, 38.7.1 For some reason not sluggish today...

So I haven't seen Thunderbird behave poorly the last few days. What I did was run "Repair Folder" on each folder I have. The same session did not improve, IIRC, so I promptly forgot about it.. but the next day the slowness wasn't there. There really should be a button to repair all folders... and maybe some kind of check for "slow to access a folder", which would trigger a suggestion to the user to repair it (similar to how Compress Folders works)