Maximise feed performance

You can generally get the best overall feed processing performance by following these guidelines:

1. Avoid submitting a large number of feeds with only a few records in each feed. When possible, combine the data into less frequent larger feeds.
2. Include only the products you are updating, not your entire inventory.
3. Upload one feed of the same type no more than every 20 minutes.
4. Keep file size below 10 MB.

Processing by feed type

To help ensure that updates occur in the order in which feeds are uploaded, we generally separate feeds by type, and then process them in sequence, except as noted below.

For tab-delimited text-file feeds, each seller's feeds are separated into the following types and processed one at a time within each type, except as noted:

1. Listing updates, including product, price, and inventory updates
2. Shipping confirmations
3. Order refunds (more than one can be processed at a time)

For XML feeds, each seller's feeds are separated into the following types and processed one at a time within each type, except as noted:

1. Product updates
2. Price updates
3. Inventory updates
4. Post-Order acknowledgements
5. Order refunds (more than one can be processed at a time)

If you submit multiple feeds of the same type (except refunds), they will generally be processed consecutively. However, feeds of different types can be processed at the same time. For example, if you submit 10 listing feeds and then submit one dispatch confirmation feed, the dispatch confirmation feed may begin processing before processing of the listing feeds is complete. 

Feed processing steps

Here are the basic feed processing steps for every feed you upload:

1. The feed waits its turn in the queue if you have submitted one or more previous feeds of the same type (except refunds), and processing of all of the feeds is not complete.
2. After all previous feeds have been processed, the new feed is set up for processing.
3. The feed is processed and the updates submitted in the feed are made.
4. Any feed errors are recorded in the processing report for the feed.

One key to maximising the overall performance of your feeds is reducing the number of times steps 1, 2, and 4 happen for your feeds as a whole. Each step adds to processing time, and step 2 can take as long for a small feed as it does for a larger feed.