When I googled "best practices peer code review rate", I found lots of hits that provide best practices for how to conduct a peer code review, but nothing came up for determining a good peer code review rate.
Our team has neither required nor consistently implemented peer code reviews in the past. We're trying to rectify that. However, we don't want to create a process that creates a bottleneck, so I'm assuming that declaring a code review is required for 100% of final commits is a bad idea.
The Question: Is there a best practice or generally accepted percentage of final commits (or other metric) that is used for selecting commits for peer code review?