Ryuta Kamizono 497e52f8c2 Don't round off subseconds unless necessary ... Currently, if `:datetime` type has a precision, type casting always does round off subseconds regardless of whether necessary or not, it is a bit slow. Since #34970, `t.timestamps` with `precision: 6` by default, so `pluck(:created_at)` in newly created app will always be affected by the round off. This avoids the round off if possible, it makes `pluck(:created_at)` about 25% faster. https://gist.github.com/kamipo/e029539f2632aee9f5e711fe66fc8842 Before (0a87d7c9dd with postgresql adapter): ``` Warming up -------------------------------------- users.pluck(:id) 344.000 i/100ms users.pluck(:name) 336.000 i/100ms users.pluck(:created_at) 206.000 i/100ms Calculating ------------------------------------- users.pluck(:id) 3.620k (± 8.5%) i/s - 18.232k in 5.077316s users.pluck(:name) 3.579k (± 9.4%) i/s - 17.808k in 5.020230s users.pluck(:created_at) 2.069k (± 8.0%) i/s - 10.300k in 5.019284s ``` Before (0a87d7c9dd with mysql2 adapter): ``` Warming up -------------------------------------- users.pluck(:id) 245.000 i/100ms users.pluck(:name) 240.000 i/100ms users.pluck(:created_at) 180.000 i/100ms Calculating ------------------------------------- users.pluck(:id) 2.548k (± 9.4%) i/s - 12.740k in 5.066574s users.pluck(:name) 2.513k (± 8.0%) i/s - 12.480k in 5.011260s users.pluck(:created_at) 1.771k (±11.2%) i/s - 8.820k in 5.084473s ``` After (this change with postgresql adapter): ``` Warming up -------------------------------------- users.pluck(:id) 348.000 i/100ms users.pluck(:name) 357.000 i/100ms users.pluck(:created_at) 254.000 i/100ms Calculating ------------------------------------- users.pluck(:id) 3.628k (± 8.2%) i/s - 18.096k in 5.024748s users.pluck(:name) 3.624k (±12.4%) i/s - 17.850k in 5.020959s users.pluck(:created_at) 2.567k (± 7.0%) i/s - 12.954k in 5.081153s ``` After (this change with mysql2 adapter): ``` Warming up -------------------------------------- users.pluck(:id) 268.000 i/100ms users.pluck(:name) 265.000 i/100ms users.pluck(:created_at) 207.000 i/100ms Calculating ------------------------------------- users.pluck(:id) 2.586k (±10.9%) i/s - 12.864k in 5.050546s users.pluck(:name) 2.543k (±10.2%) i/s - 12.720k in 5.067726s users.pluck(:created_at) 2.263k (±14.5%) i/s - 10.971k in 5.004039s ```		2019-05-28 22:50:36 +09:00
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active_model	Don't round off subseconds unless necessary	2019-05-28 22:50:36 +09:00
active_model.rb	Bump license years for 2019	2018-12-31 10:24:38 +07:00