Why am I charged for a pay-as-you-go instance I have not used?
Pay-as-you-go instances are billed based on how long they exist, not on message volume or consumer activity. When you create an instance, dedicated brokers and storage are immediately allocated and billing starts. Charges continue until you release the instance.
Billing formula
Total fees = Instance price x Service timeFor example, if your instance runs for 3 days before you release it, you pay for 72 hours of service time, regardless of whether any messages were produced or consumed.
How to stop charges
Release the instance. The following actions do not stop billing:
Stopping producers and consumers
Deleting topics
These actions leave the underlying broker and storage resources allocated, so charges continue to accrue.
Can I pause billing without releasing the instance?
No. There is no way to pause or suspend billing. As long as the instance exists, you are charged.
How is a topic-based instance converted to a partition-based instance?
You can no longer purchase ApsaraMQ for Kafka instances by topic specification. All instances now use partition specification.
Regardless of whether your instance was originally purchased by topic or partition specification, upgrades and downgrades now use partition specification only. When you upgrade or downgrade a topic-based instance, it is automatically converted using the following rules.
Conversion formula
Total partitions after conversion = Partitions included in the specification + Additional topics purchased x Conversion coefficientThe result is rounded up to the nearest integer.
Conversion coefficients
| Billing method | Conversion coefficient |
|---|---|
| Subscription | 23.913 |
| Pay-as-you-go | 45.045 |
Worked example
A subscription Standard Edition instance has the following configuration:
Bandwidth: 20 MB/s
Topics in the specification: 50
Additional topics purchased: 10
After conversion:
1,000 + 10 x 40.602 = 1,407 partitionsFor partition quotas included in each specification, see Billing rules.
Shortfall protection
If your actual partition usage exceeds the converted total, Alibaba Cloud provides the extra partitions at no charge. For example, if the conversion yields 1,000 partitions but you are using 1,100, Alibaba Cloud supplements the 100-partition difference free of charge.
Post-conversion quotas
After conversion, topic and group quotas are updated based on the partition count:
| Resource | New quota |
|---|---|
| Topics | Equal to the total number of partitions |
| Groups | Equal to the total number of partitions x 2 |
Why am I charged by peak traffic?
Generally, billing is either hardware-based or service-based. In the hardware-based billing mode, it is difficult to bill an instance based on actual service usage. In the service-based billing mode, the instance is billed based on actual service usage.
What does peak traffic measure?
Peak traffic defines the overall data processing capability of your instance, not just network bandwidth. Selecting a peak traffic tier provisions the throughput capacity of the entire cluster.
Daily processing capability
Calculate the minimum daily processing capability from peak traffic:
Data processing capability = Peak traffic x DurationExample: An instance with 30 MB/s peak traffic can process at least 2.47 TB per day:
30 MB/s x 60 s x 60 min x 24 h / 1024 / 1024 = 2.47 TB/day| Peak traffic | Minimum daily processing capability |
|---|---|
| 20 MB/s | ~1.65 TB/day |
| 30 MB/s | ~2.47 TB/day |
| 60 MB/s | ~4.94 TB/day |
| 120 MB/s | ~9.89 TB/day |
Actual processing capability may exceed these minimums.
Why am I charged for additional partitions?
Open-source Apache Kafka clusters suffer significant performance degradation beyond about 1,000 partitions. ApsaraMQ for Kafka eliminates this limitation -- a topic can have an unlimited number of partitions without performance loss.
However, additional partitions beyond your resource plan consume broker resources, so you are billed for these extra partitions accordingly.
How does the connector feature affect my bill?
The connector feature is built on EventBridge and Function Compute. Both services appear as separate line items on your bill:
| Service | Billing status |
|---|---|
| EventBridge | In public preview, free of charge |
| Function Compute | Billed separately. See Billing overview. |
This applies to the new version of the connector feature. For the previous version, see Overview.