Understanding Historical Node


I am trying to understand how historical node works internally.

I understand Historical node would have data in segment in memory, but i am trying to understand how much data would historical node would bring from deep storage and keep in memory. Is it based on most recent task completion what is notified from coordinator ?

And based on rule what is set on cordinator would it remove the data from memory ?



Hey Akhilesh,

The historicals download all active segments from deep storage to their local disks and then memory map them. After that point, the OS controls what specific data pages will be cached in memory at any particular time. Wikipedia has some info at: https://en.wikipedia.org/wiki/Page_cache