How to identify the time taken by each web service going from Magento to LS Central?
All Commerce service calls are logged in Magento in root/var/log/omniclient.log. You can see all requests, responses, and time taken by each request in the same file. Based on these values you will be able to identify which API is taking the most execution time and debugging can be performed accordingly.
How to identify the delay in basket calculation (cart, checkout, or both)?
Basket calculation helps to calculate final cart total in Magento, and it is based on product prices, taxes, and discounts coming from LS Central . The reason for that is obvious, as all price values corresponding to different discount scenarios may not be available in Magento itself.
In Magento admin, there is a configuration to choose related to basket calculation which dictates when to do the basket calculation. You can choose between every cart update, once on checkout, or both. As this process is on the heavier side, we recommend using once on checkout. You can verify the var/log/omniclient.log file with the keyword OneListCalculate to see the number of times this request is triggered, and the time taken to generate a response.
The ImageGetById web service does not fetch updated images, if the size is passed in the request.
This is a known issue in LS Central where updated images are not received if passed in the request. A solution is being workded on. Meanwhile, to get an updated image, you can skip sending the size parameter in ImageGetById so that it fetches an updated image every time.
Why are SOAP requests slow in Magento developer mode?
SOAP requests from eCommerce – Magento might be slow if you are running Magento in developer mode. In production mode, since WSDL caching is enabled, it will be fetched from cache instead of reloading on every call separately which obviously adds a lot of overhead.