On Sat Feb 24 2018 11:32:05 GMT-0500 (Eastern Daylight Time), Aki Tuomi <aki.tuomi at dovecot.fi> wrote:>> On 23 February 2018 at 23:12 Tanstaafl <tanstaafl at libertytrek.org> wrote: >> Ok, so, I'm still unclear... >> >> what cache are we talking about? Are you saying that there is a limit to >> how many emails dovecot can store in a single... 'folder'?> Dovecot has cache for commonly fetched fields. This is called > dovecot.index.cache. The maximum file size for the cache is about 4G, > the maximum offset is 0x40000000 * 4, because all offsets are divided by > 4. If the cache file becomes full, there are things you can do.. > > 1. you can rm the cache file and hope it does not get full again too > fast. 2. remove some mailsOk, so... I'm *still* unclear, and please understand I'm not trying to be difficult, but I want/need to understand this. One thing not helping is I don't have a working dovecot setup I can access to go peek at the filesystem, which would probably let me answer this for myself. When you say 'commonly fetched fields', can you confirm this means it is simply the number of emails that can cause the problem? Is this index file kept on a per *folder* basis? Or per user/account? If it is per folder, then it is much less of a problem, and could be worked around simply by moving messages around (say, archiving). Thanks again
On 13.03.2018 13:40, Tanstaafl wrote:> On Sat Feb 24 2018 11:32:05 GMT-0500 (Eastern Daylight Time), Aki Tuomi > <aki.tuomi at dovecot.fi> wrote: >>> On 23 February 2018 at 23:12 Tanstaafl <tanstaafl at libertytrek.org> wrote: >>> Ok, so, I'm still unclear... >>> >>> what cache are we talking about? Are you saying that there is a limit to >>> how many emails dovecot can store in a single... 'folder'? >> Dovecot has cache for commonly fetched fields. This is called >> dovecot.index.cache. The maximum file size for the cache is about 4G, >> the maximum offset is 0x40000000 * 4, because all offsets are divided by >> 4. If the cache file becomes full, there are things you can do.. >> >> 1. you can rm the cache file and hope it does not get full again too >> fast. 2. remove some mails > Ok, so... I'm *still* unclear, and please understand I'm not trying to > be difficult, but I want/need to understand this. One thing not helping > is I don't have a working dovecot setup I can access to go peek at the > filesystem, which would probably let me answer this for myself. > > When you say 'commonly fetched fields', can you confirm this means it is > simply the number of emails that can cause the problem?Yes> Is this index file kept on a per *folder* basis? Or per user/account?Yes> If it is per folder, then it is much less of a problem, and could be > worked around simply by moving messages around (say, archiving).It can help. But if you are not accessing all the mails e.g. migrating them, you can usually just rm the cache file and it'll probably won't grow fast back.> Thanks againAki
On Tue Mar 13 2018 07:42:31 GMT-0400 (Eastern Standard Time), Aki Tuomi <aki.tuomi at dovecot.fi> wrote:>> Is this index file kept on a per *folder* basis? Or per user/account?> YesYes... per folder? Or per user?>> If it is per folder, then it is much less of a problem, and could be >> worked around simply by moving messages around (say, archiving).> It can help. But if you are not accessing all the mails e.g. migrating > them, you can usually just rm the cache file and it'll probably won't > grow fast back.So, how would doing this impact performance? If it doesn't much, then maybe a simple script to test the size and delete when it gets larger than (whatever you like)? Thanks Aki!