As I mentioned in this post, WAF is the most crucial topic to understand to master how SSDs work, and get the most out of your drives. Write amplification (henceforth just WAF) can happen at different levels of the software stack. For instance, databases have write amplification because there are writes that aren’t directly user…
Test procedure If you are just doing some quick benchmarking or just getting started with FIO, check out the FIO Basics post. Have you ever wondered how the spec sheet performance numbers are measured on an enterprise or data center SSD? Want to make totally awesome graphs like the one below? To measure SSD performance…
Fio (flexible io tester) is what the pros and storage industry insiders use to benchmark drives in Linux. Fio is insanely powerful, confusing, and detailed; it can perform just about any sort of io generation one can think of. I’m going to give a few quick examples of how you can use it to run some quick…
This was originally written for the Chia blog here. Summary/TL;DR HDDs (hard disk drives) have moving parts and are subject to failure from mechanical wear and tear through regular use, and external environmental factors like temperature. Use SMART to monitor the drive’s health to look for uncorrectable errors and reallocated sectors for indications of predictive…
I see a fair amount of confusion from folks in our industry getting some simple terms mixed up – durability, endurance, quality, and reliability. Durability: The probability of data not being lost in a storage system. This is generally expressed in “nines”, where 99.99% or “four nines” durability means on an annual basis, the system…
When new interns came into our group at Intel in the non-volatile memory solutions group (NSG), the first thing I would do is take them to a whiteboard and explain how SSDs work, the first concept being WAF. WAF (Write Amplification Factor) is arguably the most critical concept in SSDs, and I observe even senior…
