For a long time, storage devices were much slower than CPUs. A hard disk had to physically move a read/write head and wait for the correct sector to rotate underneath it. That mechanical delay dominated everything else, so software did not need an especially efficient way to keep the device busy. SSDs removed the moving parts. SATA SSDs became much faster, but requests from multiple CPU cores still pass through one shared command queue. The cores must coordinate through this

Today, data is growing at an exponential rate, and the need to analyze and execute queries in near real time on petabytes of data has pushed OLAP (Online Analytical Processing) engines to evolve well beyond their batch-oriented origins. Historically, OLAP systems were designed to process large datasets in batch mode, with efficient query execution treated as a secondary concern. Modern workloads, however, increasingly demand that OLAP engines behave more like OLTP (Online Tra