Comment 3 for bug 223964

It seems that a lot of time is spent talking to the SMTP server. On forster, it takes a few seconds to just send the e-mails. When setting send_email to false on staging, so that send-bug-notifications.py do all its work, except for talking to the SMTP server, it takes less than a second: https://pastebin.canonical.com/4785/

On forster, a similar notification about the same bug took around 8 seconds to send out.

The main reason we see send-bug-notifications.py taking longer than normal, is that quite a lot people are subscribing to all Ubuntu bugs. Since most of our bug notifications are about Ubuntu bugs, the run time increases a bit with each subscriber.

Our best bet is probably to send the same copy of the bug notification to all Ubuntu subscribers; so that we talk to the SMTP server only once, no matter how many Ubuntu subscribers there are.

This would have been easy, if we didn't set the To header to the e-mail we're sending to. The SMTP might be able to inject this header, but we'll have to check. Another option is to change the To address to be the bug address. This is something I think we should do anyway, since it's more correct.