Comment by psanford
7 years ago
The author says low TTLs are bad because of latency but never attempts to quantify how much latency we are actually talking about. Its hard to know how outraged I'm supposed to be without actually seeing the numbers.
It seems that a lot of sites are ok with slightly higher latencies if it means greater operational flexibility.
Latency is dependent on many things. DNS server location - accessing my website from australia will take 500ms for DNS lookup (or twice as much if I'm using cnames). If this is not cached somewhere, that's 500ms every few seconds with those <1minute TTLs. If I'm on GPRS, or similar, that will add a bunch more hundreds of ms to every useless DNS resolution, incl. unpredictable variability.
So there's no single latency to report.