Round Trip Times

Silktide loads your pages in a real browser and measures how long it takes for a message to travel from the browser to each server your page uses and back again. This delay is called the round trip time, or RTT, and it affects every file your page downloads.

Why this matters

Round trip time is a tax on everything a page does. A browser makes many requests to load a typical page, and each one pays the round trip cost before any content arrives - often several times over, because requests depend on each other. On a high-latency connection, even a small page feels slow, and every visitor experiences that wait on every visit.

The usual cause is physical distance: data traveling between a visitor in one country and a server in another cannot beat the speed of light. If your servers are far from your audience, your round trip times are high for everyone.

How to fix it

Serve your content through a , which keeps copies of your files on servers around the world. Visitors download from a nearby server instead of your origin, which is usually the single biggest RTT reduction available.
Reduce the number of different servers your page depends on. Each extra domain - fonts, analytics, widgets - adds its own round trips before its content can load.
If most of your audience is in one region, host your website there.

You cannot eliminate round trip time entirely, only reduce it.

How Silktide tests this

Load the page in a real browser and record every server the page communicates with.
Measure the round trip time to each server.
Report each server with its measured RTT in milliseconds, slowest first, along with the longest RTT observed for the page.
Grade the result by the longest RTT: under 50 ms is good, and anything over 200 ms is considered poor.

Troubleshooting

The RTT looks worse than what I measure myself

Round trip time depends on where the measurement is made. Silktide tests from its own location, which may be farther from your servers than you are. That is useful information in itself: visitors in other regions experience something similar. A evens this out for everyone.

Third-party servers have high RTTs

You cannot move someone else's server, but you can decide whether to depend on it. If a third-party service consistently shows high round trip times, consider whether you need it, or whether it can load after your own content.