An OSS accelerator is a cache layer that reduces read latency for data accessed over the internal network. This topic describes how to create an accelerator, configure its cache capacity, and delete it when it is no longer needed.
The OSS accelerator feature is in public preview. The feature is available for public preview in the following regions: China (Hangzhou), China (Shanghai), China (Beijing), China (Ulanqab), China (Shenzhen), and Singapore.
Constraints
The accelerated endpoint supports internal network access only. To cache OSS data accessed over the Internet, use Alibaba Cloud CDN instead.
Cached data is stored as a single replica. If the cache hardware fails, data must be prefetched again from OSS, and access speed decreases until the prefetch completes.
Cache capacity can be modified only once per hour. For example, if you modify the capacity at 08:10:00, the next modification is allowed after 09:10:00.
Create an accelerator
Creating an accelerator involves three steps: configuring the accelerator, defining an acceleration path, and optionally creating a batch prefetch task.
Step 1: Configure the accelerator
Log on to the OSS console.
In the left-side navigation pane, click Buckets. On the Buckets page, find and click the target bucket.
In the left-side navigation pane, choose Bucket Settings > OSS Accelerator.
On the OSS Accelerator page, click Create Accelerator.
In the Note dialog box, read the terms of service and click Next.
In the Create Accelerator panel, select a Zone supported in the region where the bucket is located, set the Capacity, and click Next.
Cache capacity can be modified only once per hour (see Constraints). If you find the capacity is misconfigured immediately after creation, delete the accelerator, create a new one, and set the correct capacity.
Capacity sizing guidance: Set the cache capacity to cover your hot data volume with room for growth. For example, if your bucket contains 50 GB of hot data and usage is expected to grow 20–30% over the coming months, set the capacity to 70–80 GB.
Step 2: Configure an acceleration path
In the Create an accelerated path panel, configure the following parameters, then click Next. In the Confirm Billable Items dialog box, click Confirm.
| Parameter | Description |
|---|---|
| Acceleration policy | Controls which files the accelerator caches. Paths: specify up to 10 directory paths; only files whose paths start with a specified path are accelerated. Choose this when you need to accelerate a small number of critical directories and want to minimize cost. Entire Bucket: accelerate all files in the bucket. Choose this when all files require high-speed access and cost is not a constraint. |
| Synchronous cache warmup | Controls whether data written via the accelerated endpoint is simultaneously written to the accelerator space. See When to enable synchronous cache warmup for guidance. |
When to enable synchronous cache warmup
When synchronous cache warmup is enabled, data written through the accelerated endpoint is written to both the OSS bucket and the accelerator space. Subsequent reads via the accelerated endpoint retrieve data directly from the accelerator, reducing latency. When using a regular OSS endpoint, only the OSS bucket is accessed — not the accelerator space.
| Enable | Disable | |
|---|---|---|
| Access pattern | Frequent reads and writes | Mostly writes, rare reads |
| Latency requirement | High real-time performance required | Low latency not critical |
| Data volume | Manageable storage size | Large data volume with high storage costs |
| User experience | Sensitive to performance | Cost is the priority |
Step 3: Create a batch prefetch task (optional)
The batch prefetch feature asynchronously imports OSS data into the high-performance cluster storage, so subsequent reads experience lower latency. If you do not need batch prefetch, review the billing information and click OK to complete the accelerator creation.
Modify the cache capacity of an accelerator
Cache capacity can be modified only once per hour (see Constraints).
Log on to the OSS console.
In the left-side navigation pane, click Buckets. On the Buckets page, find and click the target bucket.
In the left-side navigation pane, choose Bucket Settings > OSS Accelerator. In the Actions column, click View Details.
In the Basic Information area, click the
icon next to Capacity.In the Edit OSS Accelerator panel, modify the Capacity value and click OK.
Confirm the modification when prompted.
Delete an accelerator
Deleting an accelerator clears only the cached data. Data stored in the OSS bucket is not affected.
Log on to the OSS console.
In the left-side navigation pane, click Buckets. On the Buckets page, find and click the target bucket.
In the left-side navigation pane, choose Bucket Management > OSS Accelerator.
Delete the accelerator using one of the following methods:
In the accelerator list, click Delete in the Actions column.
Click View Details, go to the Basic Information area, and click the
icon in the upper-right corner.
In the dialog box that appears, enter the accelerator name and click OK.
What's next
Use the accelerated endpoint with common OSS tools and SDKs. For more information, see Use an accelerator.