On 29.12.2011, at 15.36, Jan-Frode Myklebust wrote:
> On Thu, Dec 29, 2011 at 02:55:40PM +0200, Timo Sirainen wrote:
>>>
>>> I.e. find all maildir-files:
>>>
>>> - with size in the name ("*,S=*")
>>> - modified before I enabled zlib plugin
>>
>> As long as it doesn't find any already compressed mails..
>
> Can't I trust that no mails with timestamp before I enabled compression
> are uncompressed? Or will dovecot compress old messages keeping old
> timestamp when copying messages between folders, or something like that?
It's possible that a user saves a mail with an old IMAP INTERNALDATE (=file's
mtime), which is already compressed. You could use ctime, but that could skip
mails whose flags have been changed since compression.
> I want to avoid reading every file to check if it's compressed
> already, as that will add ages to an already slow process..
You could use mtime, and just before compressing the mail check if it's already
compressed. That won't add much overhead.
>>> - compress them
>>> - add the Z suffix
>>
>> Make sure there's also :2, suffix already. If someone hasn't logged in for a
>> while there are such files in new/ directory.
>
> So,
> find /var/vmail -type f -name "*,S=*:2*" -mtime +6 -exec gzip -S Z -6
> '{}' +
>
>
> Right ? I don't care too much if I miss on a few percent of the files..
Yes.
