A power supply, when suddenly turned off, bleeds voltage slowly. Attached electronics experience a gradual voltage decline from 5V to 3.3V and eventually to zero. The problem is that microcontrollers and microprocessors don’t know how to behave with under-voltage. Their behavior and flash memory integrity is not defined. Flash memory can even be erased. Here I outline my attempts to achieve an efficient logic-level power supply.
Given a cluster computing rig of twenty-eight processors, each can have either a USB 2.0 or microSD local flash storage. Which type of flash and maker is the fastest? Make the wrong choice and the cluster is painfully slow. Not all microSD cards or USB drives are made the same, and interestingly random read and write speeds vary wildly. Here I test several storage configurations with striking benchmark results.
Let’s build a 112-core 1.2GHz A53 cluster with 56GB of DDR3 RAM and 584GiB of high-availability distributed file storage, running at most 200W. The goal is to use cluster computing to perform fast Apache Spark operations on Big Data, and all on-prem for a fraction of what cloud computing costs.