How to send large amount of data to Google Ads Customer Match API?

[Chetan Patil]

Hi all,

I'm working on uploading a large set of CRM email IDs (~10 million) to Google Ads using the Customer Match API, following the official guide here: https://developers.google.com/google-ads/api/docs/remarketing/audience-segments/customer-match/get-started.

Given the volume, I’ve split the data into 10 separate jobs with 1 million operations each. These OfflineUserDataJobs are submitted sequentially by my code. However, after a few jobs run successfully, I start encountering CONCURRENT_MODIFICATION errors. While I’ve implemented a retry mechanism, some jobs still fail intermittently.

Could you please advise on the best practices for efficiently and reliably uploading large datasets like this? I'm also looking for ways to speed up the overall process if possible.

Thanks in advance for your support!

Best regards,

Chetan Patil

[Google Ads API and AdWords API Forum]

Hi chetan,

Thank you for reaching out to the Google Ads API support team.

I understand that you have encountered a "CONCURRENT_MODIFICATION" error on your end while uploading CRM email IDs. In general, the CONCURRENT_MODIFICATION error occurs due to multiple processes that are trying to update the same entity at the same time. This also includes updating the entity in Google Ads UI while updating via the API as well. We recommend waiting for about 30 seconds, then retry the request.

That being said, you’ll need to ensure that only one operation is performed against an entity at each moment and slow down on the consolidated repeated mutates against the same entity into a single request to avoid this issue altogether. Please give this a try and let us know if you have any additional concerns.