On an R80+ SMS all policy install events are logged to a special file $FWDIR/log/install_policy.elg with timestamps. In particular try seeking out **##PERF_MSG_IDENTIFY##** records in that file, as they appear to have the duration information you need, but it is not exactly easy reading:
**##PERF_MSG_IDENTIFY##** {"duration_data":[{"duration":0.4473197529999826,"name":"duration_of_code_generation#A-GW-Cluster"},{"duration":4.560813636999992,"name":"duration_of_policy_commit#A-GW-Cluster"},{"duration":0.9066284540000029,"name":"duration_of_policy_compilation#A-GW-Cluster"},{"duration":0.7535922519999899,"name":"duration_of_policy_transfer#A-GW-Cluster"}]}&CURRENTVERCMP
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