@madhur
From what you told me this is all I know about your environment.
If you read the link above, specially the part
Details you should always include
This would be very helpfull in helping you. I kinda get the sum of what your talking about. I just set mine as shown below. Its a drop down, in the stream that was created. See the red box.
I’m running Graylog 4.0.5, ES 7.10 and MongDB 4.2 All on one server. It has 1 TB storage, 10 GB RAM, and 10 CPU’s. It handles 30 million files a day = about 30 GB per day. No problems
I hope this helps.