On Thu, 20 Jul 2023 16:39:59 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org> wrote:
>>> Here's with the same parameters as the one you are using: >> >> I don't understand why there is such a difference. I have replicated similar >> results on several other devices: >> >> Apple M1: >> >> Benchmark Mode Cnt Score Error Units >> ByteArray.readByte thrpt 5 1418606.665 ± 2308.711 ops/ms >> ByteArray.readByteFromBuffer thrpt 5 879084.678 ± 20981.303 ops/ms >> ByteArray.readInt thrpt 5 1404164.063 ± 4845.412 ops/ms >> ByteArray.readIntFromBuffer thrpt 5 829768.843 ± 8730.467 ops/ms >> ByteArray.readLong thrpt 5 1400713.660 ± 1924.752 ops/ms >> ByteArray.readLongFromBuffer thrpt 5 825721.508 ± 4146.961 ops/ms >> >> >> >> Intel Celeron N5105: >> >> Benchmark Mode Cnt Score Error Units >> ByteArray.readByte thrpt 5 927248.807 ± 29630.442 ops/ms >> ByteArray.readByteFromBuffer thrpt 5 448374.359 ± 3210.571 ops/ms >> ByteArray.readInt thrpt 5 719143.935 ± 183584.747 ops/ms >> ByteArray.readIntFromBuffer thrpt 5 398578.488 ± 100.058 ops/ms >> ByteArray.readLong thrpt 5 742555.147 ± 13006.710 ops/ms >> ByteArray.readLongFromBuffer thrpt 5 398771.660 ± 1673.524 ops/ms >> >> >> AMD Ryzen 7 5800X: >> >> Benchmark Mode Cnt Score Error Units >> ByteArray.readByte thrpt 5 1784096.905 ± 47611.535 ops/ms >> ByteArray.readByteFromBuffer thrpt 5 992974.747 ± 19389.011 ops/ms >> ByteArray.readInt thrpt 5 1719368.129 ± 70606.284 ops/ms >> ByteArray.readIntFromBuffer thrpt 5 919654.075 ± 9292.283 ops/ms >> ByteArray.readLong thrpt 5 1719873.280 ± 18441.122 ops/ms >> ByteArray.readLongFromBuffer thrpt 5 921992.992 ± 6439.747 ops/ms > > On a newer processor/OS (Alder Lake/Ubuntu 22.04) I see a bit more difference: > > > Benchmark Mode Cnt Score Error Units > ByteArray.readByte thrpt 5 680397.046 ± 27504.022 ops/ms > ByteArray.readByteFromBuffer thrpt 5 576449.569 ± 3633.135 ops/ms > ByteArray.readInt thrpt 5 685419.089 ± 6740.268 ops/ms > ByteArray.readIntFromBuffer thrpt 5 542887.418 ± 2863.907 ops/ms > ByteArray.readLong thrpt 5 687949.037 ± 3510.613 ops/ms > ByteArray.readLongFromBuffer thrpt 5 548120.950 ± 5461.145 ops/ms > > > But still far from 2x. For full disclosure, I'm running the benchmark using the JDK microbenchmark support. My JMH version is a bit behind. I've updated it to 1.35 (which is the latest I see being used around here) and getting similar results. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/14636#discussion_r1269722383
