IMAP Server performance, large mailboxes

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IMAP Server performance, large mailboxes

Post by airbear » Fri Nov 20, 2015 4:43 pm

I have recently migrated a number of large mailboxes (1GB - 8GB) into my MailEnable 8.55 server. I am finding that the IMAP server is very slow to service IMAP clients opening these mailboxes.

Mailbox size: 811MB
Total files: 4981
Inbox files: 3732

Logging into the above mailbox using SquirrelMail IMAP client takes approx 3 minutes.

I notice that my MEMIS.exe service is dead and will not run (I have a MailEnable upgrade scheduled to hopefully resolve this). Will the indexes created by MEMIS.exe assist with servicing IMAP clients more rapidly? Is there anything I can do to improve the response times with large mailboxes?


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Re: IMAP Server performance, large mailboxes

Post by MailEnable-Ian » Mon Nov 23, 2015 12:13 am


The first step is upgrading version 8.55 to version 8.61 located at the link below which is free upgrade and contains fixes to MailEnable cores services that you need to apply.

The Indexing service (MEMIS.exe) is not used by IMAP for indexing messages. Its used solely for the Web mail "Search" option. Upgrade first then reassess the IMAP behavior.

Ian Margarone
MailEnable Support

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