rate of sending emails

This morning, there was a gateway mixup - the SMTP firewall rule was pointing to a disabled gateway, so the emails did not go through. After I changed it, checking the number of mails pending with sudo qshape incoming active deferred found that the mails were going at the rate of approximately 20,000 per hour. Of course, services like yahoo which had rate limiting would queer the pitch, but otherwise this was the rate for a 1 Mbps line, I believe.