We are on AEM 6.5.7 and using formsservice alogn with reader extension service to generate PDF, PDFs are getting generated from XDP placed in shared drive within 3 sec but as soon as Reader extension code is added PDF generation time shoots to more than 15 min.
@manugupta02Reader Extensions need a certificate (ares) which you have as far as i can tell. In the past I have seen such behaviour when the server applying the REs cannot connect to the Internet to download initial CRLs (Certificate Revocation Lists). Your Windows server might have had a chance to do an initial load or was configured to ignore them. I have not seen this since Adobe LiveCycle and I am not sure how the current AEM Forms OSGi has this implemented. Maybe someone else can advise what to do in that case.