how data is received client -> socket -> n/w thread(lightweight) -> req queue -> i/o thread(crc check & append to commit log[.index and .log file]) -> resp queue -> n/w-> socket

purgatory map -> used for req until data is replicated

how data is fetched client -> socket -> n/w -> req queue -> i/o thread (fetch ranges are calcualted with .index) -> res queue -> n/w -> socket

purgatory map -> waits until is arrived based on consumer config

also follows zero copy - meaning data fetched from file directly to n/w thread - mostly page cached

if not cached -> may need to use tiered storage