[horde] Error: No connection to server

Mon Nov 7 08:34:08 UTC 2011

Simon Brereton <simon.brereton at buongiorno.com> a écrit :

> On 4 November 2011 12:12, Ronan SALMON <rsalmon at mbpgroup.com> wrote:
>>
>> Simon Brereton <simon.brereton at buongiorno.com> a écrit :
>>
>>> On 4 November 2011 10:39, Jan Schneider <jan at horde.org> wrote:
>>>>
>>>> Zitat von Simon Brereton <simon.brereton at buongiorno.com>:
>>>>
>>>>> On 4 November 2011 10:11, Jan Schneider <jan at horde.org> wrote:
>>>>>>
>>>>>> Zitat von Simon Brereton <simon.brereton at buongiorno.com>:
>>>>>>
>>>>>>> Hi
>>>>>>>
>>>>>>> I have one installation of Horde that is available on three different
>>>>>>> URLs
>>>>>>> (https://webmail.example.com, https://webmail.example.net and
>>>>>>> https://webmail.example.org) and although users are encouraged to log
>>>>>>> in
>>>>>>> on
>>>>>>> the domain corresponding to their email, because the authentication is
>>>>>>> against the IMAP server, it would work on any URL.
>>>>>>>
>>>>>>> I now have one user who is getting:
>>>>>>>        Error when communicating with the server.[Thu 03 Nov 2011
>>>>>>> 02:04:28
>>>>>>> PM EST]
>>>>>>> and
>>>>>>>        The server was unable to generate the message list.[Thu 03 Nov
>>>>>>> 2011
>>>>>>> 02:04:29 PM EST]
>>>>>>>
>>>>>>> This happens for one user regardless of the domain they log in on.  It
>>>>>>> doesn't happen for any of the other users..  Unless changed users are
>>>>>>> presented with the Portal page - which doesn't load for this use.
>>>>>>>  Changing
>>>>>>> the URL to imp/ starts to load IMP and then errors above occur.  Ditto
>>>>>>> changing it to kronolith/
>>>>>>>
>>>>>>> The logs aren't very forth-coming.  Here is one login session for the
>>>>>>> user..
>>>>>
>>>>>>> Googling the errors, I saw a comment by Jan to check the apache logs -
>>>>>>> those turned up this.
>>>>>>>
>>>>>>>
>>>>>>> [Thu Nov 03 17:35:01 2011] [error] [client 77.101.63.17] PHP Fatal
>>>>>>> error:
>>>>>>>  Allowed memory size of 134217728 bytes exhausted (tried to allocate
>>>>>>> 24
>>>>>>> bytes) in /usr/share/horde4/kronolith/lib/Kronolith.php on line 698,
>>>>>>> referer: https://webmail.example.net/imp/
>>>>>>> [Thu Nov 03 18:06:53 2011] [error] [client 38.104.167.66] PHP Fatal
>>>>>>> error:
>>>>>>>  Allowed memory size of 134217728 bytes exhausted (tried to allocate
>>>>>>> 64
>>>>>>> bytes) in /usr/share/php/Horde/Date.php on line 1055, referer:
>>>>>>>
>>>>>>>
>>>>>>> https://webmail.example.net/login.php?horde_logout_token=TrLYKvGPlLzBE4nfF2NO4JSVSUZGs4nfF2NO4JSVSUZG6Zo6hB0&logout_reason=4
>>>>>>> [Thu Nov 03 18:07:25 2011] [error] [client 38.104.167.66] PHP Fatal
>>>>>>> error:
>>>>>>>  Allowed memory size of 134217728 bytes exhausted (tried to allocate
>>>>>>> 75
>>>>>>> bytes) in /usr/share/php/Horde/Date.php on line 1054, referer:
>>>>>>> https://webmail.example.net/imp/
>>>>>>> [Thu Nov 03 18:07:27 2011] [error] [client 38.104.167.66] PHP Fatal
>>>>>>> error:
>>>>>>>  Allowed memory size of 134217728 bytes exhausted (tried to allocate
>>>>>>> 75
>>>>>>> bytes) in /usr/share/php/Horde/Date.php on line 1054, referer:
>>>>>>> https://webmail.example.net/imp/
>>>>>>
>>>>>> Well, the error message can't be clearer.
>>>>>
>>>>> For you maybe - but why would only this user have a problem with
>>>>> Date.php?  Are you suggesting I raise my PHP memory limit?
>>>>
>>>> It's not a problem with Date.php. But the limit has to exceed
>>>> *somewhere*.
>>>> It happens to be in that file.
>>>> And yes, that's what I'm suggesting.
>>>
>>> This doesn't explain why it's this one user.  This doesn't explain why
>>> the problem persists if I force all the users to log out and it still
>>> affects that one user.  This doesn't explain why it persists even
>>> across an apache restart.  This doesn't explain why that one user is
>>> still having an error today despite the fact that the memory limit
>>> error doesn't appear in the logs today.
>>>
>>> Finally, what would you suggest is a suitable memory limit for ~100
>>> users?  Currently I have 128M (which is about 7 times the php
>>> default).
>>>
>>>  456 ; Maximum amount of memory a script may consume (128MB)
>>>  457 ; http://php.net/memory-limit
>>>  458 memory_limit = 128M
>>
>> This can happen (it did happen over here) when opening a message containing
>> one (or more) big attachment.
>
>
> I'm not happy.  I'm fully prepared to believe it's my server admin
> skills and not a specific horde issue - but:
>
> a) this only happened since the upgrade yesterday
> b) it's one specific user
> c) my user-base is miniscule
> d) my apache logs are not showing the memory error today at all.
>
> I logged into the users account with Evolution - their inbox had two
> mails (out of 12) over 1 MB - 9.7 and 6.2 - so 12 mails totalling less
> than 25MB
>
> I moved those mails out of the Inbox and the issue persisted.
>
> I raised the memory limit to 256M and was able to login on horde finally
> Log out.
> return the mail to the inbox and I'm still able to log in.
>
> Questions.
> My personal mail box is well over 200 mails and is much bigger than
> 25MB - and yet I don't have a problem.  Why would one mailbox with
> 25MB cause an out of memory error and mine doesn't.
>
>
> How does this scale?  I never have more than 30 simultaneous
> connections.  How do sites cope with 1000+ users?  If you need 256MB
> memory limit for 3 users (that's all I've had today, do you need
> multiple gigabytes for 1000+ users?

No, memory_limit is for one running process only, if you 3 users  
connecting simultaneous, you'll get 3 processes.

I never experienced any problem regarding the number of messages. Some  
of my users have more than 10k messages in INBOX! It was slow with IMP  
4, but now with IMP 5 it's fine.

> Why is only one user affected when the memory limit is reached (and
> that persistently across apache restarts?
>
> Finally, I'm not comfortable with having a global memory_limit of
> 256MB for PHP applications.  However, if I add php_value memory_limit
> 256M to the .htaccess in the horde4 folder, I get an Internal server
> error.  How can I raise the limit for Horde and Horde only?

See http://wiki.horde.org/CentOS5InstallationNotes#toc11

Ronan.