Why are users with very large folders seeing slow performance when switching folders?
A number of users on my system appearing to be suffering from performance issues especially when switching between mail folders or disconnecting from the system.
Only users with very large mail folders appear to be affected.
Version 14.01 of GMS introduced support for large mail folders raising the previous 2 Gigabyte limit for an individual folder to 2 Terrabytes. As of this release there is a new globaldomainuser registry entry which can not be set from the GUI allowing control over the performance of these folders.
The variable is called MaxFolderPurgeSize. Any folder above the given size (in Kb) will NOT be purged during normal operation – i.e. during IMAP Expunge, POP QUIT or WebMail switch folder. Instead such folders are scheduled to be purged later so as not to interfere with normal operations of the client.
The values that can be given to this variable are as follows:
-1 – always defer purge.
0 – never defer purge (default setting).
>0 – defer purge if folder size is greater than size. This is the original mail folder file size before deleted items are taken into account.
Before enabling this variable for any users please ensure that the “Purge Email” setting is enabled at the domain level as it is this setting that performs the deferred purge of the folder.
Keywords:large folder purge slow performance