1. Concepts Guide
  2. Object Storage Overview
  3. Multipart Uploads

Multipart Uploads

The Object Storage service supports multipart uploads for more efficient and resilient uploads, especially for large objects.

You can perform multipart uploads using the Compute API or CLI. The Compute Web UI uses multipart uploads to upload objects larger than 64 MiB.

With multipart uploads, individual parts of an object can be uploaded in parallel to reduce the amount of time you spend uploading. Multipart uploads performed through the API can also minimize the impact of network failures by letting you retry a failed part upload instead of requiring you to retry an entire object upload.

Multipart uploads can accommodate objects that are too large for a single upload operation. For large uploads performed through the API, you have the flexibility of pausing between the uploads of individual parts, and resuming the upload when your schedule and resources allow.

Object Parts

With multipart upload, you split the object you want to upload into individual parts. Individual parts can be as large as 50 GiB. The maximum size for an uploaded object is 10 TiB.

Decide what part number you want to use for each part. Part numbers can range from 1 to 10,000. You do not need to assign contiguous numbers, but Object Storage constructs the object by ordering part numbers in ascending order.

Multipart Upload API

Before you use the multipart upload Compute API, you are responsible for creating the parts to upload. Object Storage provides API operations for the remaining steps.

A multipart upload performed using the API consists of the following steps:

  1. Initiate an upload.

  2. Upload object parts.

  3. Commit the upload.

The service also provides API operations for listing in-progress multipart uploads, listing the object parts in an in-progress multipart upload, and aborting in-progress multipart uploads initiated through the API.

Multipart Upload CLI

When you perform a multipart upload using the OCI CLI, you do not need to split the object into parts as you are required to do by the Compute API. Instead, you specify the part size of your choice, and Object Storage splits the object into parts and performs the upload of all parts automatically. You can choose to set the maximum number of parts that can be uploaded in parallel. By default, the CLI limits the number of parts that can be uploaded in parallel to three. When using the CLI, you do not have to perform a commit when the upload is complete.

You can also use the CLI to list in-progress multipart uploads, and to abort multipart uploads initiated through the API.