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plan: three items measured rather than assumed, and one of them is no… #706

Job	Run time
invariants (windows-x86_64)	4m 30s
invariants (linux-aarch64)	4m 4s
invariants (linux-x86_64)	6m 18s
invariants (macos-arm64)	2m 56s
scan (windows-x86_64)	8m 46s
scan (macos-arm64)	5m 4s
scan (linux-aarch64)	3m 57s
scan (linux-x86_64)	10m 32s
coverage (every host the table names was scanned)	6s
	46m 13s