John Mueller from Google recently shared insights with site owners on handling A/B testing during site migrations. He advised against conducting A/B tests during migrations, as this can unnecessarily prolong the process.
This topic emerged during a Google Webmaster Central hangout, where someone inquired about the impact of running an A/B test alongside a large-scale URL migration. The question addressed whether such testing could alter how Google perceives signals, potentially extending the period of site volatility.
Mueller responded extensively, advising against large-scale A/B tests during migrations. He explained that Google attempts to grasp the overall structure of a site during a migration. A clear understanding by Google allows for a smooth transfer of algorithmic signals from the old to the new site. An ongoing A/B test complicates this understanding, causing delays.
For site owners, Mueller recommends ensuring a clean signal during migrations. He suggests verifying that all old URLs redirect to their new versions, fixing any crawl errors, and avoiding changes to robots.txt that weren’t present before.
These actions help Google efficiently process a migration. It’s crucial to provide a straightforward indication that you’re transitioning from one version of a site to another to avoid delays.
You can hear Mueller’s detailed response in the video, starting at the 11:17 mark.
Mueller added that small-scale A/B testing within a site might not be an issue. However, larger-scale tests should be minimized, especially during migrations between different domains or protocol changes like HTTP to HTTPS. Such clarity allows Google to apply algorithms that move signals efficiently from the old site to the new one. Any confusion from mixed signals, such as conflicting redirects, can delay the migration process.
In summary, ensuring a clean and clear migration setup will likely result in a smoother and faster transition.
