Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
The dude you forced to leave the list last year tweeted about this problem in February, so it was noticed back then, apparently Noel said "CBF reporting the issue as the fucker would ignore me anyway, 'n if he did read it, wld prolly blame my config" I'll forward your patch and see what he says LOL On 6/10/14, Timo Sirainen wrote: > On 9.6.2014, at 20.49, Andy Dills wrote: > Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing large mails? I can't think of any reasonable explanation for this. >>> >>> Most likely solved by: http://hg.dovecot.org/dovecot-2.2/rev/6a9508d28d34 >>> [1] >>> >>> Strange that it didn't break more commonly or that more people weren't >>> complaining about it.. The bug has been there since v2.2.7. >> >> Thank you Timo. This patch did indeed correct the problem, we had no >> problem doing full syncs with the problematic accounts after >> implementing this. >> >> Is it perhaps something that only happens with directory/proxy >> environments? I'm surprised it hasn't been mentioned before, I figured >> it was something particular to our implementation since nobody else was >> mentioning it, until you did. >> >> Fascinating to me that it only affects Outlook as well. I don't >> understand the code well enough to grasp the impact of the bug, so if >> somebody has a minute to share an explanation that would be cool. > > Only happened when using Dovecot proxy. Only happened if client sent a > command while another long running command was already sending data. So > basically if Outlook started downloading a large mail on background and user > clicked another mail, the already running FETCH was stopped because Outlook > sent another FETCH command to the same connection. I guess Outlook was the > only client to do that. >
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 9.6.2014, at 20.49, Andy Dills wrote: >>> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging >>> IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing >>> large mails? I can't think of any reasonable explanation for this. >> >> Most likely solved by: http://hg.dovecot.org/dovecot-2.2/rev/6a9508d28d34 [1] >> >> Strange that it didn't break more commonly or that more people weren't >> complaining about it.. The bug has been there since v2.2.7. > > Thank you Timo. This patch did indeed correct the problem, we had no > problem doing full syncs with the problematic accounts after > implementing this. > > Is it perhaps something that only happens with directory/proxy > environments? I'm surprised it hasn't been mentioned before, I figured > it was something particular to our implementation since nobody else was > mentioning it, until you did. > > Fascinating to me that it only affects Outlook as well. I don't > understand the code well enough to grasp the impact of the bug, so if > somebody has a minute to share an explanation that would be cool. Only happened when using Dovecot proxy. Only happened if client sent a command while another long running command was already sending data. So basically if Outlook started downloading a large mail on background and user clicked another mail, the already running FETCH was stopped because Outlook sent another FETCH command to the same connection. I guess Outlook was the only client to do that.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 06/09/2014 05:21, Timo Sirainen wrote: > On 5.6.2014, at 17.38, Timo Sirainen wrote: > >> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging >> IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing >> large mails? I can't think of any reasonable explanation for this. > > Most likely solved by: http://hg.dovecot.org/dovecot-2.2/rev/6a9508d28d34 [1] > > Strange that it didn't break more commonly or that more people weren't > complaining about it.. The bug has been there since v2.2.7. Thank you Timo. This patch did indeed correct the problem, we had no problem doing full syncs with the problematic accounts after implementing this. Is it perhaps something that only happens with directory/proxy environments? I'm surprised it hasn't been mentioned before, I figured it was something particular to our implementation since nobody else was mentioning it, until you did. Fascinating to me that it only affects Outlook as well. I don't understand the code well enough to grasp the impact of the bug, so if somebody has a minute to share an explanation that would be cool. Andy - ANDY DILLS - XECUNET, LLC 5744-R Industry Lane Frederick MD 21704 www.xecu.net [2] P: 301-682-9972 P: 1-877-XECUNET F: 240-215-0351 Twitter [3] Facebook [4] - Links: -- [1] http://hg.dovecot.org/dovecot-2.2/rev/6a9508d28d34 [2] http://www.xecu.net/ [3] https://twitter.com/Xecunet [4] http://www.facebook.com/xecunet
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 5.6.2014, at 17.38, Timo Sirainen wrote: > Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging > IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing large > mails? I can't think of any reasonable explanation for this. Most likely solved by: http://hg.dovecot.org/dovecot-2.2/rev/6a9508d28d34 Strange that it didn't break more commonly or that more people weren't complaining about it.. The bug has been there since v2.2.7.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 06/09/2014 02:58 AM, Charles Marcus wrote: > On 6/7/2014 10:46 AM, Kilburn Abrahams wrote: >> These users >> have 50GB+ mailboxes using IMAP. > > What mailbox format (maildir? dbox? mbox?)? Maildir++. I have got most Outlook users to remove delete items so the size ~ 30GB with the exception of 2 users that I want to keep for testing. I switched to fetch headers. It seemed to reduce the error a bit but I don't know if this is factor of mail reduction or headers. Either way, there is a regression in 2.2.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 6/7/2014 10:46 AM, Kilburn Abrahams wrote: These users have 50GB+ mailboxes using IMAP. What mailbox format (maildir? dbox? mbox?)?
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Am 07.06.2014 16:46, schrieb Kilburn Abrahams: > I can confirm also that since upgrading from 2.1.16 to 2.2.13 that > Outlook 2013 (don't have previous versions to test) is throwing strange > errors when users send emails. This predominantly happens when sending > but has happened when they compose a long email then send. These users > have 50GB+ mailboxes using IMAP. > > I will try the fetch headers and report back. > > The Outlook errors we are getting is "The operation failed. The > messaging interfaces returned an unknown error. Please restart Outlook". > > So I can confirm there is problem, as one of the users who use > Thunderbird with an equally large mailbox and does not have problems. > > Kilburn you mean copy to "sent" imap sent folder , after sent via smtp perhaps i find time to test this myself too, however 50 GB of Mailbox is "not very wise" to have anyway, what are youre "offline" sync policies at that mailboxes, or better to say ,what are defaults at outlook 2013 with syncing such large mailboxes in imap mode, Thunderbird per default does full sync , and gives the chance to configure by folder. At last, dont expect Outlook as good imap client, in very prime its the client of exchange, other features like imap are "on top". > > On 06/07/2014 12:25 AM, Andy Dills wrote: >> We just upgraded from 2.1.16 to 2.2.13, and we have been have horrendous >> troubles with outlook since the upgrade. >> >> For users with large mailboxes, they are unable to sync their folders. >> Perhaps this is specifically because of the problem you are mentioning Timo. >> >> The only solution we could come up with for now was to configure outlook to >> only fetch headers and not bodies, when syncing. For the most part, bringing >> up individual messages is fine, haven't seen that fail. So, with that tweak >> to the outlook config, things are working error-free again for our >> users...but it was certainly an unexpected situation to tackle. >> >> Also, we found a marked improvement connecting via SSL on 993 than we do >> unencrypted on 143. >> >> I can definitely confirm 100% there is a regression in dovecot 2.2 that >> severely impacts the performance of outlook (but works great with everything >> else). >> >> Let me know if I can help you track this down Timo. >> >> Andy >> >> Sent from my iPhone >> >>> On Jun 5, 2014, at 1:40 PM, Timo Sirainen wrote: >>> On 5.6.2014, at 20.23, Robert Schetterer wrote: Am 05.06.2014 17:02, schrieb Timo Sirainen: > On 5.6.2014, at 17.41, Martin Rabl wrote: > >> Am 05.06.2014 16:38, schrieb Timo Sirainen: >>> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) >>> hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're >>> FETCHing large mails? I can't think of any reasonable explanation for >>> this. >> how large? > I don't know yet if the mail size is even relevant. At least one hang was > caused by downloading ~55 MB mail where it stopped just before the last > 400 kB. > > I find it strange that v2.2 has been out for a long time and nobody > before this complained about any hangs. 55 MB mail may are rare ,i can test it ,but it will need some time ( old outlook install on clean new windows system) perhaps anyone has an existing setup which could do it faster >>> Happens also with smaller mails, for example 3 MB and I think there were >>> also even smaller ones like 1 MB. I see that once Outlook tried to download >>> the same 3 MB mail 3 times and it stopped reading it when it had 400 kB >>> left, but the 4th time succeeded. Dovecot sent exactly the same data with >>> the same TCP packet boundaries all times (at least to Dovecot proxy - would >>> have to look with tcpdump further to see if proxy does something >>> differently..) >>> >>> Anyway, nobody in general has had trouble with Dovecot v2.2 and Outlook >>> 2007/2010? Maybe the problem is something else, although strange if it >>> started happening only immediately after Dovecot upgrade. Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
I can confirm also that since upgrading from 2.1.16 to 2.2.13 that Outlook 2013 (don't have previous versions to test) is throwing strange errors when users send emails. This predominantly happens when sending but has happened when they compose a long email then send. These users have 50GB+ mailboxes using IMAP. I will try the fetch headers and report back. The Outlook errors we are getting is "The operation failed. The messaging interfaces returned an unknown error. Please restart Outlook". So I can confirm there is problem, as one of the users who use Thunderbird with an equally large mailbox and does not have problems. Kilburn On 06/07/2014 12:25 AM, Andy Dills wrote: > We just upgraded from 2.1.16 to 2.2.13, and we have been have horrendous > troubles with outlook since the upgrade. > > For users with large mailboxes, they are unable to sync their folders. > Perhaps this is specifically because of the problem you are mentioning Timo. > > The only solution we could come up with for now was to configure outlook to > only fetch headers and not bodies, when syncing. For the most part, bringing > up individual messages is fine, haven't seen that fail. So, with that tweak > to the outlook config, things are working error-free again for our > users...but it was certainly an unexpected situation to tackle. > > Also, we found a marked improvement connecting via SSL on 993 than we do > unencrypted on 143. > > I can definitely confirm 100% there is a regression in dovecot 2.2 that > severely impacts the performance of outlook (but works great with everything > else). > > Let me know if I can help you track this down Timo. > > Andy > > Sent from my iPhone > >> On Jun 5, 2014, at 1:40 PM, Timo Sirainen wrote: >> >>> On 5.6.2014, at 20.23, Robert Schetterer wrote: >>> >>> Am 05.06.2014 17:02, schrieb Timo Sirainen: On 5.6.2014, at 17.41, Martin Rabl wrote: > Am 05.06.2014 16:38, schrieb Timo Sirainen: >> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) >> hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're >> FETCHing large mails? I can't think of any reasonable explanation for >> this. > how large? I don't know yet if the mail size is even relevant. At least one hang was caused by downloading ~55 MB mail where it stopped just before the last 400 kB. I find it strange that v2.2 has been out for a long time and nobody before this complained about any hangs. >>> 55 MB mail may are rare ,i can test it ,but it will need some time ( old >>> outlook install on clean new windows system) >>> perhaps anyone has an existing setup which could do it faster >> Happens also with smaller mails, for example 3 MB and I think there were >> also even smaller ones like 1 MB. I see that once Outlook tried to download >> the same 3 MB mail 3 times and it stopped reading it when it had 400 kB >> left, but the 4th time succeeded. Dovecot sent exactly the same data with >> the same TCP packet boundaries all times (at least to Dovecot proxy - would >> have to look with tcpdump further to see if proxy does something >> differently..) >> >> Anyway, nobody in general has had trouble with Dovecot v2.2 and Outlook >> 2007/2010? Maybe the problem is something else, although strange if it >> started happening only immediately after Dovecot upgrade.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Am 06.06.2014 16:25, schrieb Andy Dills: > I can definitely confirm 100% there is a regression in dovecot 2.2 that > severely impacts the performance of outlook (but works great with everything > else). please be exact in describing what Outlook version, i did not notice any problem testing Outlook 2013, anyway thx for informing Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
We just upgraded from 2.1.16 to 2.2.13, and we have been have horrendous troubles with outlook since the upgrade. For users with large mailboxes, they are unable to sync their folders. Perhaps this is specifically because of the problem you are mentioning Timo. The only solution we could come up with for now was to configure outlook to only fetch headers and not bodies, when syncing. For the most part, bringing up individual messages is fine, haven't seen that fail. So, with that tweak to the outlook config, things are working error-free again for our users...but it was certainly an unexpected situation to tackle. Also, we found a marked improvement connecting via SSL on 993 than we do unencrypted on 143. I can definitely confirm 100% there is a regression in dovecot 2.2 that severely impacts the performance of outlook (but works great with everything else). Let me know if I can help you track this down Timo. Andy Sent from my iPhone > On Jun 5, 2014, at 1:40 PM, Timo Sirainen wrote: > >> On 5.6.2014, at 20.23, Robert Schetterer wrote: >> >> Am 05.06.2014 17:02, schrieb Timo Sirainen: >>> On 5.6.2014, at 17.41, Martin Rabl wrote: >>> Am 05.06.2014 16:38, schrieb Timo Sirainen: > Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging > IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing > large mails? I can't think of any reasonable explanation for this. how large? >>> >>> I don't know yet if the mail size is even relevant. At least one hang was >>> caused by downloading ~55 MB mail where it stopped just before the last 400 >>> kB. >>> >>> I find it strange that v2.2 has been out for a long time and nobody before >>> this complained about any hangs. >> >> 55 MB mail may are rare ,i can test it ,but it will need some time ( old >> outlook install on clean new windows system) >> perhaps anyone has an existing setup which could do it faster > > Happens also with smaller mails, for example 3 MB and I think there were also > even smaller ones like 1 MB. I see that once Outlook tried to download the > same 3 MB mail 3 times and it stopped reading it when it had 400 kB left, but > the 4th time succeeded. Dovecot sent exactly the same data with the same TCP > packet boundaries all times (at least to Dovecot proxy - would have to look > with tcpdump further to see if proxy does something differently..) > > Anyway, nobody in general has had trouble with Dovecot v2.2 and Outlook > 2007/2010? Maybe the problem is something else, although strange if it > started happening only immediately after Dovecot upgrade.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Am 06.06.2014 00:39, schrieb Joseph Tam: > Timo Sirainen writes: > >> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) >> hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're >> FETCHing large mails? I can't think of any reasonable explanation for >> this. > > It's a shot in the dark, but I had a problem with a different client, > where semi-large attachments was problematic. > > It turned out to be a TCP scaling problem. If a router/firewall drops > packets with a TCP scaling option set, the endpoints disagree on how many > outstanding non-ACK packets are allowed, resulting in timeouts. > > http://support.microsoft.com/kb/935400 > http://en.wikipedia.org/wiki/TCP_window_scale_option > > The Microsoft KB does hint those versions of Outlook may be affected, but > I can't figure out why there would be a difference between Dovecot 2.1 > and 2.2. TCp scaling is a problem since many years and well known for delivery problems with MTA's if there are broken network devices between both sides just disable it *anywhere* and be happy signature.asc Description: OpenPGP digital signature
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Timo Sirainen writes: Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing large mails? I can't think of any reasonable explanation for this. It's a shot in the dark, but I had a problem with a different client, where semi-large attachments was problematic. It turned out to be a TCP scaling problem. If a router/firewall drops packets with a TCP scaling option set, the endpoints disagree on how many outstanding non-ACK packets are allowed, resulting in timeouts. http://support.microsoft.com/kb/935400 http://en.wikipedia.org/wiki/TCP_window_scale_option The Microsoft KB does hint those versions of Outlook may be affected, but I can't figure out why there would be a difference between Dovecot 2.1 and 2.2. Joseph Tam
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 5.6.2014, at 20.23, Robert Schetterer wrote: > Am 05.06.2014 17:02, schrieb Timo Sirainen: >> On 5.6.2014, at 17.41, Martin Rabl wrote: >> >>> Am 05.06.2014 16:38, schrieb Timo Sirainen: Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing large mails? I can't think of any reasonable explanation for this. >>> how large? >> >> I don't know yet if the mail size is even relevant. At least one hang was >> caused by downloading ~55 MB mail where it stopped just before the last 400 >> kB. >> >> I find it strange that v2.2 has been out for a long time and nobody before >> this complained about any hangs. >> > > 55 MB mail may are rare ,i can test it ,but it will need some time ( old > outlook install on clean new windows system) > perhaps anyone has an existing setup which could do it faster Happens also with smaller mails, for example 3 MB and I think there were also even smaller ones like 1 MB. I see that once Outlook tried to download the same 3 MB mail 3 times and it stopped reading it when it had 400 kB left, but the 4th time succeeded. Dovecot sent exactly the same data with the same TCP packet boundaries all times (at least to Dovecot proxy - would have to look with tcpdump further to see if proxy does something differently..) Anyway, nobody in general has had trouble with Dovecot v2.2 and Outlook 2007/2010? Maybe the problem is something else, although strange if it started happening only immediately after Dovecot upgrade.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Am 05.06.2014 17:02, schrieb Timo Sirainen: > On 5.6.2014, at 17.41, Martin Rabl wrote: > >> Am 05.06.2014 16:38, schrieb Timo Sirainen: >>> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging >>> IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing >>> large mails? I can't think of any reasonable explanation for this. >>> >> how large? > > I don't know yet if the mail size is even relevant. At least one hang was > caused by downloading ~55 MB mail where it stopped just before the last 400 > kB. > > I find it strange that v2.2 has been out for a long time and nobody before > this complained about any hangs. > 55 MB mail may are rare ,i can test it ,but it will need some time ( old outlook install on clean new windows system) perhaps anyone has an existing setup which could do it faster Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
On 5.6.2014, at 17.41, Martin Rabl wrote: > Am 05.06.2014 16:38, schrieb Timo Sirainen: >> Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging >> IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing >> large mails? I can't think of any reasonable explanation for this. >> > how large? I don't know yet if the mail size is even relevant. At least one hang was caused by downloading ~55 MB mail where it stopped just before the last 400 kB. I find it strange that v2.2 has been out for a long time and nobody before this complained about any hangs.
Re: [Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Am 05.06.2014 16:38, schrieb Timo Sirainen: Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing large mails? I can't think of any reasonable explanation for this. how large? -- Viele Grüße, Martin Rabl
[Dovecot] Outlook 2007 & 2010 hangs in v2.2?
Has anybody noticed Outlook 2007 & 2010 (but apparently not 2013) hanging IMAP connections with Dovecot v2.2 (but not v2.1) when they're FETCHing large mails? I can't think of any reasonable explanation for this.
