What are fragments?

When you upload an object in the multipart upload mode, the object is divided into several parts, which are stored as fragments in OSS. After you upload all the fragments to the OSS server, you can call CompleteMultipartUpload to combine the parts into a complete object.

  • Fragments are also generated when you transfer objects by using OSS management tools that support multipart upload or download.
  • You can call CompleteMultipartUpload to combine the fragments into a complete object. For more information on how to use MultipartUpload, see Introduction.
  • You can regularly clear unnecessary fragments by setting the lifecycle management. It is used to clear the fragments for which CompleteMultipartUpload is not complete for a long term in the bucket to reduce the consumption of space. For the detailed procedure, see Set lifecycle.
  • A fragment cannot be read before it is combined with other fragments into an object. To delete a bucket, you must delete the objects and fragments stored in the bucket first. Fragments are mainly generated by multipart upload tasks. For more information, see Introduction.


  1. Log on to the OSS console.
  2. In the left-side bucket list, click the name of the target bucket to open the overview page of the bucket.
  3. Click the Files tab.
  4. Click the Fragments to open the Fragments page.
  5. Delete the part files.
    • To delete all the part files in a bucket, click Delete All.
    • To delete some of the part files in a bucket, select or search for the expected part files and click Delete.
  6. In the dialog box that appears, click OK.