We have an app that is having issues, and it looks like it's ArcServer but it could be a network issue. And I've scoured the internet for answers but an still stumped. The service draws fast from the endpoint when you tell it to preview or use the JS viewer. However, when querying right from the REST endpoint it's a pig, query all records and it seems to hang and die. Query 200 records and it runs fairly fast but slower then it should. We are using the Esri-Leaflet API and It can be fast locally, but from outside the firewall it's slow and draws in patches before it stops, before it finishes.
Any ideas or clues?
Layer: streams (ID: 1) endpoint
ArcServer 10.6,, MS Server 2016, 16GB ram