Error Fetching http headers
The problem is related to the too long action on the Salesforce side. As result script exceeds waiting timeout and it causes the described issue.
Instructions
This issue has 2 possible solutions:
Increase your server timeout and allow wait response from the Salesforce longer
Decrease records count our podule process in each execution
The best way is use combination of both these solutions
1. Increase your server timeout and allow wait response from the Salesforce longer
Change the default_socket_timeout param in your php.ini config file and increase defined value
2. Decrease records count our podule process in each execution
Go to our module “General“ config page and decreate the “Batch size” param here:
You may need to restart module consumers to take affect
Some articles about the same issue:
SOQL: No response from the server error
Error fetching http headers in SoapClient