test(uffd): MAP_POPULATE backing file #5445
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We use example uffd handlers in performance tests to measure the population latency. We do not want for it to be diluted by the page faults in the backing file. Using an already populated backing file makes the measurement more precise. Signed-off-by: Nikita Kalyazin <[email protected]>
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## main #5445 +/- ##
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Coverage 82.79% 82.79%
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Files 263 263
Lines 27301 27301
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Hits 22603 22603
Misses 4698 4698
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Changes
Mmap the backing file in the UFFD handlers with
MAP_POPULATE.Reason
We use example UFFD handlers in performance tests to measure the population latency. We do not want for it to be diluted by the page faults in the backing file. Using an already populated backing file makes the measurement more precise.
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