Budgets are an often an essential part of how you manage your cloud bill. The purpose of Ternary Budgets is to:

Allow you track usage for given subset of cloud assets and measure against an arbitrary level of spend.
Define a scope for a key: labelvalue pair and assign a budget to it
Set thresholds for when you want to receive alerts
Get a quick view of cloud assets most in danger of going up against budget
Import budgets you might have set in the google billing console

You can access the Budgets page from the Cost Assist heading in the left hand navigation.

Create New Budget

Here you can define:

Budget Name
AmountScope Key: this is the cloud asset you want the budget assigned to ie. Project ID
Scope Value: this is the value of the key. ie gcp-project-1
Measure: netCost, cost (gross), customNetCustom (if you have custom rate cards configured in Ternary)

What do the thresholds do?

The percentage thresholds will send you an alert when you've reached a certain percentage of your budget.

What is included in net cost?

Net cost will include any credits you receive from Google which are outlined below.

Credits are any one-time promotions, committed use discounts, or any other type of discounts you may be getting from Google. The purpose of giving you the option to create a budget with or without credits, is often you want to know how a particular scope is trending. Including credits can sometimes obfuscate the trend.

Here's what Ternary considers as credits (from google documentation)

"Credit types include:

COMMITTED_USAGE_DISCOUNT: Resource-based committed use contracts purchased for Compute Engine in return for deeply discounted prices for VM usage.
COMMITTED_USAGE_DISCOUNT_DOLLAR_BASE: Spend-based committed use contracts purchased for services in exchange for your commitment to spend a minimum amount.
DISCOUNT: The discount credit type is used for credits earned after a contractual spending threshold is reached. Note that in the Cloud Billing reports available in the Cloud Console, the discount credit type is listed as Spending based discounts (contractual).
FREE_TIER: Some services offer free resource usage up to specified limits. For these services, credits are applied to implement the free tier usage.
PROMOTION: The promotion credit type includes Google Cloud Free Trial and marketing campaign credits, or other grants to use Google Cloud. When available, promotional credits are considered a form of payment and are automatically applied to reduce your total bill.
RESELLER_MARGIN: If you are a reseller, the reseller margin credit type indicates the Reseller Program Discounts earned on every eligible line item.
SUBSCRIPTION_BENEFIT: Credits earned by purchasing long-term subscriptions to services in exchange for discounts.
SUSTAINED_USAGE_DISCOUNT: The sustained use discounts credit type is an automatic discount that you earn for running specific Compute Engine resources for a significant portion of the billing month."

MTD Spend

Simply spend occurred to date.

Forecast

This is a linear extrapolation based on your MTD spend. Note, if you have bursty workloads that occur either earlier or later in the month, the forecast could over or under estimate the expected spend.

Variance

This is simply [Forecast] - [Budget]. This is is meant to highlight the scopes that are most in danger of blowing through your budget.

Budget Graph - Current Month

This tells you the following information:

What is your budget for the month - indicated by the horizontal blue line
The dark shaded area indicates your MTD spend.
The light shaded area is Ternary's forecast extrapolation of your spend based on your usage so far. Ternary calculates your forecasted end of month spend as:

   Current month-to-date spend + (average spend over past 30-days * days remaining in month)

The red shaded area shows up if your actual or extrapolated spend is above your budget

Budget Graph - Daily Trends

This is an overlay of multiple months of daily spend. The purpose of this graph is for you to be able to see how your workloads are trending month over month. That is, is it the case that most of your spend is front or backloaded? Or is it the case that your usage is relatively flat?

This is intended to let you see if you have crossed a threshold, if it actually means that you are in danger of going over your budget or not. i.e. if it turns out that your usage is always front loaded for the month, then it's likely that you don't have anything to worry about.

This dark shaded area is the current month spend.

The lighter shades are different months daily spend overlaid on top of each other.

If you hover over the graph you can see that days spend over the past 6 months.

Budget Graph - Monthly Trends

This is intended to help you see what your monthly spend trend has been over the past few months and how that compares to the budget you have set. This can be used as a good benchmark to inform whether or not your budget needs revision.