alt Hacker News> WALs, and related low-level logging details, are critical for database systems that care deeply about durability on a single system. But the modern database isn’t like that: it doesn’t depend on commit-to-disk on a single system for its durability story. Commit-to-disk on a single system is both unnecessary (because we can replicate across storage on multiple systems) and inadequate (because we don’t want to lose writes even if a single system fails).
And then a bug crashes your database cluster all at once and now instead of missing seconds, you miss minutes, because some smartass thought "surely if I send request to 5 nodes some of that will land on disk in reasonably near future?".
I love how this industry invents best practices that are actually good then people just invent badly researched reasons to just... not do them.
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The biggest lie we’ve been told is that databases require global consistency and a global clock. Traditional databases are still operating with Newtonian assumptions about absolute time, while the real world moves according to Einstein’s relativistic theory, where time is local and relative. You dont need global order, you dont need global clock.
Happens all the time (the ignores best practices because it’s convenient or ‘just because’ to do something different), literally everywhere including normal society.
Frankly, it’s shocking anything works at all.
> "surely if I send request to 5 nodes some of that will land on disk in reasonably near future?"
That would be asynchronous replication. But IIUC the author is instead advocating for a distributed log with synchronous quorum writes.