Limits and performance metrics of OSS

Bandwidth

The following table describes the maximum bandwidth of a single Alibaba Cloud account in different regions.

If the maximum bandwidth is reached, new requests are throttled. When a request is throttled, the response to the request contains the x-oss-qos-delay-time: number header, in which number indicates the duration in milliseconds for which the request is throttled. For a throttled upload request, this header indicates the exact duration of throttling. For a throttled download request, this header indicates a throttling duration estimated based on the extent of throttling and the object size.

QPS

The total queries per second (QPS) for an Alibaba Cloud account is 10,000. The actual maximum QPS performance varies based on the read and write modes:

If you upload a large number of objects and the names of the objects contain sequential prefixes such as timestamps and letters, multiple object indexes may be stored in a single partition. In this case, if you send a large number of requests to query these objects, latency is increased. We recommend that you do not use object names that contain sequential prefixes if you want to upload a large number of objects. For more information about how to change sequential prefixes to random prefixes, see OSS performance best practices.

Buckets

• You can use an Alibaba Cloud account to create up to 100 buckets in the same region. If you want to create more than 100 buckets in a region based on your business requirements, go to Quota Center to submit a request.

• A bucket name must be globally unique in OSS. For more information, see Bucket naming conventions.

• After a bucket is created, you cannot change its name, region, or storage class.

• OSS does not impose limits on the capacity of a bucket.

Objects

• The size of an object that you can upload

  When you use simple upload, form upload, or append upload to upload an object, the size of the object cannot exceed 5 GB. For more information, see Simple upload, Form upload, and Append upload.

  When you use multipart upload to upload an object, the size of the object cannot exceed 48.8 TB. For more information, see Multipart upload.

• The size of an object that you can rename

  You can rename only objects whose sizes are less than or equal to 1 GB in the OSS console. If you want to rename objects whose sizes exceed 1 GB, we recommend that you use OSS SDKs or ossutil. For more information, see Rename objects.

• The number of objects that you can delete

  You can delete up to 100 objects at a time in the OSS console or up to 1,000 objects at a time by using OSS SDKs. You can delete an unlimited number of objects at a time by using ossutil or ossbrowser.

  Warning

  Deleted objects cannot be recovered. Proceed with caution.

• Overwrites of objects that have the same names

  By default, if you upload an object that has the same name as an existing object, the existing object is overwritten.

  Warning

  Overwritten objects cannot be recovered. Proceed with caution. To prevent objects from being accidentally overwritten, you can enable versioning for the bucket in which the objects are stored. You can also include the x-oss-forbid-overwrite header in upload requests and set the header to true.

Data restoration

If real-time access of Archive objects is not enabled and you want to access Archive, Cold Archive, or Deep Cold Archive objects, you must first restore the objects. A higher restoration priority indicates a shorter restoration period and higher data retrieval fees. For more information, see the OSS Billing Details section on the

OSS product page.

Domain name mapping

• If you want to map a domain name to a bucket located in a region in the Chinese mainland, you must apply for an ICP filing from the Ministry of Industry and Information Technology (MIIT).

• Up to 100 domain names can be mapped to a bucket. However, a domain name can be mapped to only one bucket.

• OSS does not impose limits on the number of domain names that can be mapped to the buckets of an Alibaba Cloud account.

Lifecycle rules

• You can configure up to 1,000 lifecycle rules for a bucket.

• Completion time

  Lifecycle rule that does not contain tags

  • For a lifecycle rule that is not based on tags, up to 1 billion lifecycle management actions, including object deletion, storage class conversion, and part expiration, can be completed within 24 hours in the following regions: China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), and Singapore. If the number of lifecycle management actions based on the lifecycle rule exceeds 1 billion, the time required to complete the actions may exceed 24 hours.

  • For a lifecycle rule that is not based on tags, up to 100 million lifecycle management actions can be completed within 24 hours in other regions. If the number of lifecycle management actions based on the lifecycle rule exceeds 100 million, the time required to complete the actions may exceed 24 hours.

  Lifecycle rule that contains tags

  • For a lifecycle rule that is based on tags, up to 500 million lifecycle management actions, including object deletion, storage class conversion, and part expiration, can be completed within 24 hours in the following regions: China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), China (Ulanqab), China (Shenzhen), and Singapore. If the number of lifecycle management actions based on the lifecycle rule exceeds 500 million, the time required to complete the actions may exceed 24 hours.

  • For a lifecycle rule that is based on tags, up to 50 million lifecycle management actions can be completed within 24 hours in other regions. If the number of lifecycle management actions based on the lifecycle rule exceeds 50 million, the time required to complete the actions may exceed 24 hours.

  Note

  If versioning is enabled for a bucket, a lifecycle management action on each object version in the bucket is counted towards the applicable limit.

Back-to-origin

• You can configure up to 20 back-to-origin rules for a bucket.

• In regions in the Chinese mainland and the China (Hong Kong) region, the default QPS and the default bandwidth for mirroring-based back-to-origin requests are 2,000 and 2 Gbit/s, respectively. In other regions, the default QPS and the default bandwidth for mirroring-based back-to-origin requests are 1,000 and 1 Gbit/s, respectively.

IMG

• Limits on images

  • Source images

    • Only JPG, PNG, BMP, GIF, WebP, TIFF, HEIC, and AVIF images are supported.

    • A source image cannot be greater than 20 MB in size.

    • For the rotate operation, the height or width of a source image cannot exceed 4,096 pixels. For other operations, the width or height of a source image cannot exceed 30,000 pixels, and the total number of pixels of the source image cannot exceed 250 million.

      The total number of pixels of a dynamic image, such as a GIF image, is calculated by using the following formula: Width × Height × Number of image frames. The total number of pixels of a static image, such as a PNG image, is calculated by using the following formula: Width × Height.

  • Resized images

    The width or height of a resized image cannot exceed 16,384 pixels. The total number of pixels of the resized image cannot exceed 16,777,216.

• Limits on image styles

  You can create up to 50 image styles for a bucket.

  Note

  If you want to create more styles based on your business requirements, contact

  technical support.

• Limits on processing capabilities

  • Per-second processing throughput (by source image)

    • The maximum throughput of image processing is 20 MB/s for the following regions: China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), and China (Shenzhen).

    • The maximum throughput of image processing for other regions is 2 MB/s.

  • QPS

    • The QPS is 50 for the following regions: China (Hangzhou), China (Shanghai), China (Beijing), China (Zhangjiakou), and China (Shenzhen).

    • The QPS for other regions is 5.

  Note

  You may want processing capabilities that exceed the preceding limits in compute intensive business applications, such as encoding WebP, AVIF, or HEIF images at a resolution higher than 1080p. To increase the processing capabilities, contact

  technical support.

Resource plans

• Resource plans that you purchase for a specific region can be used to offset the fees for resource usage only in the region.

• You cannot change the region of a purchased resource plan.

• You can purchase only one storage plan for a given period of time. However, you can upgrade the storage plan that you purchased. For more information about how to upgrade a storage plan, see Resource plans.

• You can purchase multiple transfer acceleration plans and back-to-origin traffic plans that have the same validity period to offset your fees. However, these plans cannot be upgraded or renewed.

• You can purchase multiple outbound traffic plans that have the same validity period to offset your fees. These plans can be renewed but cannot be upgraded.

• No resource plans can be used to offset API operation calling fees, data processing fees, and cross-region replication (CRR) traffic fees. You are charged these fees based on the pay-as-you-go billing method. For more information, see API operation calling fees, Data processing fees, and Traffic fees.