I've now done a non-limited comparative benchmark of master against
the patch (once again, with usage_count starting at 6, and
BM_MAX_USAGE_COUNT at 30) with a Gaussian distribution. Once again,
the distribution threshold used was consistently 5.0, causing the
patched pgbench to report for each test:
transaction type: Custom query
scaling factor: 5000
standard deviation threshold: 5.00000
access probability of top 20%, 10% and 5% records: 0.68269 0.38293 0.19741
Results are available from:
http://postgres-benchmarks.s3-website-us-east-1.amazonaws.com/3-sec-delay-gauss/
--
Peter Geoghegan