As -live instances histogram requires a fullgc, the histogram will produce all by default (which doesn't require a fullgc).

You could easily configure it by using the system property -Dcom.cloudbees.jenkins.support.impl. HeapUsageHistogram.FULLGC=true (permanent) or by running from Script Console com.cloudbees.jenkins.support.impl. HeapUsageHistogram.FULLGC=true (temporal) if you want to grab live instances.

The histogram component could be easily disabled by using the system property -Dcom.cloudbees.jenkins.support.impl. HeapUsageHistogram.DISABLE=true (permanent) or by running from Script Console com.cloudbees.jenkins.support.impl. HeapUsageHistogram.DISABLE=true (temporal).