Cost Spike Alerts can help to keep an eye on those parts of your AWS infrastructure that are prone to exceeding their defined monthly budget, or can tend to have unpredictable cost changes.
Create a Cost Spike Alert
- Log in to the Stax console
- Choose the arrow next to your organization alias to open the customer menu
- Choose Notifications
- Choose + Create Notification then choose the appropriate delivery channel from the drop-down list. In this example, Email is chosen
- Select your View and segment of interest. All Views is selected by default, but you can narrow it down further by choosing a View and segment yourself. Your user's email address will be present in the Enter email addresses field, but you can remove this and/or add others if desired
- Choose Continue to show the Configure Notifications page
- Under the Cost Run Rate Spike Alerts heading, choose Include Cost Run Rate Spike Alerts
- Enter the minimum increase (in US dollars), as well as how sensitive you want the cost spike alert to be. See Understanding Sensitivity below for more detail on how sensitivity is determined
- Choose Create Notification to finish creating the notification
How Cost Spike Notifications Work
Stax periodically checks your daily spend to see how much it is deviating compared to the last 7 days. If the deviation is above a certain threshold and amount, this is considered to be a spike.
- If your average daily spend over the last 7 days is $100 USD, but the average for today is $200 USD. With a sensitivity of Medium and minimum increase of $50 USD, you would get a spike
- If your average daily spend over the last 7 days is $100 USD, but the average for today is $200 USD. With a sensitivity of Medium and minimum increase of $250 USD, you would not get a spike because it did not exceed the minimum increase of $250 USD
- If your average daily spend over the last 7 days is $100 USD, but the average for today is $101 USD. With a sensitivity of High and minimum increase of $90 USD, you would not get a spike because the sensitivity is too high
When defining a Cost Spike Notification, a minimum cost increase and sensitivity must be nominated. These settings impact when notifications will be sent.
Firstly, if a cost spike occurs but is less than the Minimum increase in $USD specified when creating the notification, no notification will be sent.
Secondly, Stax uses the standard score (z-score) to define the sensitivity of a cost spike alert. These prescribe how sensitive Stax is to changes in the standard deviation over a rolling 7-day window, specifically:
- Low: z-score of 1.2
- Medium: z-score of 1.5
- High: z-score of 1.9