On Mon, Sep 05, 2011 at 07:19:00PM +0200, Julien Coloos wrote: > Le 05/09/2011 12:06, Bron Gondwana a écrit : > >On Mon, Sep 05, 2011 at 02:32:40PM +1000, Greg Banks wrote: > > > >> - add a 32b mailbox index header entry to track the storage in bytes > >>used by all annotations for the mailbox itself or for messages in the > >>mailbox > >Why not 64b? Admittedly hanging gigabytes of annotations off a single > >folders is probably evil, but this is the mailbox header - 4 bytes per > >mailbox to not even have to think about it is super-cheap. We keep a > >handful of "blanks" around in the header already. > > > >... > > > >> - in mailbox_commit_quota(), if the field is not "unknown", then > >>calculate the delta in usage and apply to the quota db. > > > This new field seems useful for the quota utility and when setting a > new quotaroot: it wouldn't need to check each annotation associated > to the mailbox (or messages) and would rely on that field, as it > currently does for total message size and now the number of messages > (with my patch). > I don't know what other people do with cyrus, but here those two > situations do not happen that often: > - quotaroot is usually set once upon creating the user mailbox > - quota utility is rarely used, and usually on one mailbox at a time > So maybe I am missing something, but my question would be: is it > really worth it ?
I would challenge the "usually on one mailbox at a time" theory - it's often on one quota root at a time (i.e. - a single user), but also can be used on the entire server. Or for someone with a domain quota, on all the users in a single domain. This can be quite the race condition if someone has a lot of mailboxes and a lot of traffic on said mailboxes. Short of killing their connections and blocking LMTP traffic, you can't guarantee atomicity on actions that cross multiple mailboxes. But - the new field definitely has value. I like the idea of just trusting that field in the quota utility and for regular tasks. Bron.
