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MaxCompute:Optimize the costs of data uploads and downloads

Last Updated:Mar 26, 2026

Data transfers between MaxCompute and other services are either free or billed depending on the network path. Use the following four strategies to reduce upload and download costs.

When transfers are free

Transfers over an internal network — either the cloud product interconnection network or a Virtual Private Cloud (VPC) — are not charged. If your compute resources are already on Alibaba Cloud, routing traffic through an internal network is the most direct way to eliminate transfer costs.

For network configuration details, see Endpoints.

Cost reduction strategies

Use an internal network for uploads and downloads

Route data through the cloud product interconnection network or VPC instead of the public internet. Internal network transfers carry no data transfer charge.

Use a subscription ECS instance as a download relay

If you need to download large volumes of data to a local directory, use a subscription Elastic Compute Service (ECS) instance as an intermediary:

  1. Use Tunnel to synchronize data from MaxCompute to the ECS instance.

  2. Download the data from ECS to your local directory.

For an example of exporting query results, see Examples of exporting SQL execution results.

Batch small files before uploading with Tunnel

Uploading many small files individually consumes disproportionate compute resources — each upload call carries fixed overhead regardless of payload size. To minimize this overhead, accumulate files in a local buffer and upload them in batches. When using Tunnel SDK, trigger an upload once the buffer reaches 64 MB.

Estimate bandwidth before migrating from an on-premises data center

When migrating data from an on-premises data center to MaxCompute over a physical connection, calculate the required bandwidth before provisioning the connection to avoid under- or over-provisioning.

Example: To migrate 50 TB in one day, the required bandwidth is approximately 5 Gbit/s:

50 × 1024 × 8 / (24 × 3600) = 4.7 Gbit/s

Factor in this estimate alongside connection costs when planning the migration.

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