>Time wise, a 0.1% error rate for a month means a 43 minute complete downtime. This article assumes relatively constant usage. If a service is used heavily in

>Time wise, a 0.1% error rate for a month means a 43 minute complete downtime. This article assumes relatively constant usage. If a service is used heavily in a single time zone this number could be considerably lower. The flip side of that is that it might not make sense to alert during night hours of that time zone. You wouldn't want to get paged by a single user spaming retry on an error page.