Looks like the June security update has brought along an annoying new problem. Many Google Pixel 2 XL users are reporting that after installing the update, their unit lags when they try to wake it up using the power button. The delay is significant - up to 3 seconds in some cases - and can also be observed during the fingerprint unlock process. AOD seems to be playing a role here as there's reportedly no lag when the feature is enabled. There's a dedicated thread related to the matter on Google's official Issue Tracker website, and as it currently stands, the problem has been passed...
Source: https://www.gsmarena.com/google_pixel_2_xl_users_reporting_significant_wake_up_delay_after_june_update-news-31504.php
