[Dovecot] Many messages clustered around the same date.saved value

[Joseph Tam]

Timo Sirainen wrote:

>> However, I noticed a strange thing: querying what would have been
>> deleted
>> 
>> doveadm -ftab fetch -A "date.saved" mailbox Trash savedbefore 7d
>> 
>> showed many date.saved values are clustered around the same timestamp,
>> even among different user's Trash mailbox.
>> ...
>> I can't explain why many different users would have messages with the
>> same (or closeby) date.saved value.
> 
> Which mailbox format? With Maildir the date.saved is taken from
> dovecot.index.cache file, and in some cases that might get dropped.  If
> it does, then it fallbacks to using the file's ctime.

mbox.

A further look into this reveals that the clustered date.saved values
are the earliest values for every mailbox in the system.  This timestamp
is close to the time I was testing "doveadm ... -A", so the likely
explanation is that I accidentally deleted/updated these values using
some variation of doveadm, even though I remember confining my testing
to query/search/fetch.  This appears to be a case of PEBKAC.

These "wrong" values shouldn't cause problems with expunge queries since
they err on the side of safety.

Thanks for the insight though.

Joseph Tam <jtam.home at gmail.com>