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* Measure 07047c3 again on a quiet Pi (110)eunhhu2026-09-3025-0/+96
| | | | | | | | | | The six pairs rerun once the Pi had been quiet for a minute, on the same binaries. Two pairs were still interfered (the first's before at an owner share of 0.54, the sixth at 0.73 on both sides); the four clean ones are -1.7%, -0.4%, +1.8% and +1.1%, CPU per transaction 43.25 to 42.9 us. The bank's queries are as fast or faster after, though the interference fell more on the before runs; the instruction counts stay the comparison to trust.
* Count instructions where timing cannot tell 3% apart (110)eunhhu2026-09-3062-0/+718
016's second stage passed its criterion: six interleaved pairs against ee21aec gave TPC-C (RAM, W=1) -0.6% at the median and the bank's queries 0.0% to +2.2%, no run interfered. The ranks query was slower all six times, and chasing it showed that on this Pi timing cannot separate 1-3%: two servers asked in turns disagree with themselves (ee21aec to e02bfc9 +1.6%, e02bfc9 to 481642f -1.2%, ee21aec to 481642f +2.8%), and a query whose instructions grew 0.6% ran 3.5% faster. Instructions do not move so: pcount.c counts the server's user-mode instructions with perf_event_open (no perf here), and psample.c samples where they go. ranks had grown 0.4% in instructions (the rest was where code and data landed), per_branch 3.6% and tables 20 instructions a row, which 07047c3 halved. The six pairs of 07047c3 were interfered (another session's build, load 4-12) and are kept apart, unused.