DocuSign For Salesforce - System.CalloutException: IO Exception: Exceeded max size limit of 6000000
DocuSign for Salesforce Error: System.CalloutException: IO Exception: Exceeded max size limit of 6000000 with request size 6004736.
A breach of Salesforce's 6mb heap size limit. Generally caused by an overly large document being used, but can also be caused by number of recipients, many merge fields, or other high-volume activity.
Under the DocuSign Administrator > Settings tab in Salesforce, there is an option to Enable Salesforce callout limit compensation. Checking this may allow DocuSign for Salesforce to work around this limit.
If this setting does not resolve the issue, the volume of data being processed will need to be reduced. This may mean uploading the document or applying a template in the DocuSign tagger. If working with a very large file, compressing it, flattening it, or otherwise reducing the file size will be necessary.