What is drift?
Drift is the slow, unintentional change of a value over time. In tech it most often refers to “clock drift,” where a computer’s internal clock runs a little faster or slower than the real world time, causing its time to gradually get out of sync.
Let's break it down
- Every computer has a tiny quartz crystal that ticks to keep time.
- No crystal is perfect, so each tick can be a fraction of a second off.
- Over minutes, hours, or days those tiny errors add up, making the clock drift away from the correct time.
- The amount of drift is usually measured in seconds per day (e.g., +2 seconds/day).
Why does it matter?
If devices think the wrong time, many things break: scheduled tasks may run at the wrong moment, security certificates can be seen as expired, logs become confusing, and distributed systems can lose coordination, leading to data errors or outages.
Where is it used?
- Servers and data centers need synchronized clocks for logging and transaction ordering.
- Mobile phones and IoT gadgets rely on accurate time for GPS, messaging, and sensor data.
- Cloud services use time‑sync protocols (like NTP) to keep all machines aligned.
- Financial trading platforms require microsecond precision, so they constantly monitor drift.
Good things about it
- Detecting drift can reveal hardware problems early, prompting maintenance before a failure.
- Some security systems use intentional clock drift as a “moving target” to make attacks harder.
- Understanding drift helps engineers design better time‑keeping algorithms and choose more stable hardware.
Not-so-good things
- Unchecked drift leads to missed deadlines, corrupted data, and security vulnerabilities.
- Fixing drift after it’s happened can be complex, especially in large, distributed networks.
- High‑precision hardware to reduce drift can be expensive, raising costs for small projects.