ac26c8b644
5 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Yonatan Graber
|
e1a0b79259
|
yonatang solution: a jdk8 friendly, no unsafe code, epsilon-gc friendly solution (#499)
* 1bc challenge, but one that will run using jdk 8 without unsafe and still do reasonably well. * Better hashtable * the fastest GC is no GC * cleanups * increased hash size * removed Playground.java * collision-handling allocation free hashmap * formatting |
||
Jin Cong Ho
|
32bb237091
|
Initial Submission (#389)
Co-authored-by: Gunnar Morling <gunnar.morling@googlemail.com> |
||
Vemana
|
f11fad2a68
|
Submission #5 [No bitwise tricks nor Unsafe yet; 13th place on leaderboard in local testing using evaluate2.sh] (#209)
* Linear probe for city indexing. Beats current leader spullara 2.2 vs 3.8 elapsed time. * Straightforward impl using bytebuffers. Turns out memorysegments were slower than used mappedbytebuffers. * A initial submit-worthy entry Comparison to select entries (averaged over 3 runs) * spullara 1.66s [5th on leaderboard currently] * vemana (this submission) 1.65s * artsiomkorzun 1.64s [4th on leaderboard currently] Tests: PASS Impl Class: dev.morling.onebrc.CalculateAverage_vemana Machine specs * 16 core Ryzen 7950X * 128GB RAM Description * Decompose the full file into Shards of memory mapped files and process each independently, outputting a TreeMap: City -> Statistics * Compose the final answer by merging the individual TreeMap outputs * Select 1 Thread per available processor as reported by the JVM * Size to fit all datastructure in 0.5x L3 cache (4MB/core on the evaluation machines) * Use linear probing hash table, with identity of city name = byte[] and hash code computed inline * Avoid all allocation in the hot path and instead use method parameters. So, instead of passing a single Object param called Point(x, y, z), pass 3 parameters for each of its components. It is ugly, but this challenge is so far from Java's idioms anyway * G1GC seems to want to interfere; use ParallelGC instead (just a quick and dirty hack) Things tried that did not work * MemorySegments are actually slower than MappedByteBuffers * Trying to inline everything: not needed; the JIT compiler is pretty good * Playing with JIT compiler flags didn't yield clear wins. In particular, was surprised that using a max level of 3 and reducing compilation threshold did nothing.. when the jit logs print that none of the methods reach level 4 and stay there for long * Hand-coded implementation of Array.equals(..) using readLong(..) & bitmask_based_on_length from a bytebuffer instead of byte by byte * Further tuning to compile loop methods: timings are now consistenctly ahead of artsiomkorzun in 4th place. There are methods on the data path that were being interpreted for far too long. For example, the method that takes a byte range and simply calls one method per line was taking a disproportionate amount of time. Using `-XX:+AlwaysCompileLoopMethods` option improved completion time by 4%. ============= vemana =============== [20:55:22] [lsv@vemana]$ for i in 1 2 3 4 5; do ./runTheir.sh vemana; done; Using java version 21.0.1-graal in this shell. real 0m1.581s user 0m34.166s sys 0m1.435s Using java version 21.0.1-graal in this shell. real 0m1.593s user 0m34.629s sys 0m1.470s Using java version 21.0.1-graal in this shell. real 0m1.632s user 0m35.893s sys 0m1.340s Using java version 21.0.1-graal in this shell. real 0m1.596s user 0m33.074s sys 0m1.386s Using java version 21.0.1-graal in this shell. real 0m1.611s user 0m35.516s sys 0m1.438s ============= artsiomkorzun =============== [20:56:12] [lsv@vemana]$ for i in 1 2 3 4 5; do ./runTheir.sh artsiomkorzun; done; Using java version 21.0.1-graal in this shell. real 0m1.669s user 0m38.043s sys 0m1.287s Using java version 21.0.1-graal in this shell. real 0m1.679s user 0m37.840s sys 0m1.400s Using java version 21.0.1-graal in this shell. real 0m1.657s user 0m37.607s sys 0m1.298s Using java version 21.0.1-graal in this shell. real 0m1.643s user 0m36.852s sys 0m1.392s Using java version 21.0.1-graal in this shell. real 0m1.644s user 0m36.951s sys 0m1.279s ============= spullara =============== [20:57:55] [lsv@vemana]$ for i in 1 2 3 4 5; do ./runTheir.sh spullara; done; Using java version 21.0.1-graal in this shell. real 0m1.676s user 0m37.404s sys 0m1.386s Using java version 21.0.1-graal in this shell. real 0m1.652s user 0m36.509s sys 0m1.486s Using java version 21.0.1-graal in this shell. real 0m1.665s user 0m36.451s sys 0m1.506s Using java version 21.0.1-graal in this shell. real 0m1.671s user 0m36.917s sys 0m1.371s Using java version 21.0.1-graal in this shell. real 0m1.634s user 0m35.624s sys 0m1.573s ========================== Running Tests ====================== [21:17:57] [lsv@vemana]$ ./runTests.sh vemana Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10000-unique-keys.txt Using java version 21.0.1-graal in this shell. real 0m0.150s user 0m1.035s sys 0m0.117s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10.txt Using java version 21.0.1-graal in this shell. real 0m0.114s user 0m0.789s sys 0m0.116s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-1.txt Using java version 21.0.1-graal in this shell. real 0m0.115s user 0m0.948s sys 0m0.075s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-20.txt Using java version 21.0.1-graal in this shell. real 0m0.113s user 0m0.926s sys 0m0.066s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-2.txt Using java version 21.0.1-graal in this shell. real 0m0.110s user 0m0.734s sys 0m0.078s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-3.txt Using java version 21.0.1-graal in this shell. real 0m0.114s user 0m0.870s sys 0m0.095s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-boundaries.txt Using java version 21.0.1-graal in this shell. real 0m0.113s user 0m0.843s sys 0m0.084s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-complex-utf8.txt Using java version 21.0.1-graal in this shell. real 0m0.121s user 0m0.852s sys 0m0.171s * Improve by a few % more; now, convincingly faster than 6th place submission. So far, only algorithms and tuning; no bitwise tricks yet. Improve chunking implementation to avoid allocation and allow finegrained chunking for the last X% of work. Work now proceeds in two stages: big chunk stage and small chunk stage. This is to avoid straggler threads holding up result merging. Tests pass [07:14:49] [lsv@vemana]$ ./test.sh vemana Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10000-unique-keys.txt Using java version 21.0.1-graal in this shell. real 0m0.152s user 0m0.973s sys 0m0.107s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10.txt Using java version 21.0.1-graal in this shell. real 0m0.113s user 0m0.840s sys 0m0.060s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-1.txt Using java version 21.0.1-graal in this shell. real 0m0.107s user 0m0.681s sys 0m0.085s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-20.txt Using java version 21.0.1-graal in this shell. real 0m0.105s user 0m0.894s sys 0m0.068s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-2.txt Using java version 21.0.1-graal in this shell. real 0m0.099s user 0m0.895s sys 0m0.068s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-3.txt Using java version 21.0.1-graal in this shell. real 0m0.098s user 0m0.813s sys 0m0.050s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-boundaries.txt Using java version 21.0.1-graal in this shell. real 0m0.095s user 0m0.777s sys 0m0.087s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-complex-utf8.txt Using java version 21.0.1-graal in this shell. real 0m0.112s user 0m0.904s sys 0m0.069s * Merge results from finished threads instead of waiting for all threads to finish. Not a huge difference overall but no reason to wait. Also experiment with a few other compiler flags and attempt to use jitwatch to understand what the jit is doing. * Move to prepare_*.sh format and run evaluate2.sh locally. Shows 7th place in leaderboard | # | Result (m:s.ms) | Implementation | JDK | Submitter | Notes | |---|-----------------|--------------------|-----|---------------|-----------| | 1 | 00:01.588 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thomaswue.java)| 21.0.1-graal | [Thomas Wuerthinger](https://github.com/thomaswue) | GraalVM native binary | | 2 | 00:01.866 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_merykitty.java)| 21.0.1-open | [Quan Anh Mai](https://github.com/merykitty) | | | 3 | 00:01.904 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java)| 21.0.1-graal | [Roy van Rijn](https://github.com/royvanrijn) | | | | 00:02.398 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ebarlas.java)| 21.0.1-graal | [Elliot Barlas](https://github.com/ebarlas) | | | | 00:02.724 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_obourgain.java)| 21.0.1-open | [Olivier Bourgain](https://github.com/obourgain) | | | | 00:02.771 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_algirdasrascius.java)| 21.0.1-open | [Algirdas Ra__ius](https://github.com/algirdasrascius) | | | | 00:02.842 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_vemana.java)| 21.0.1-graal | [Vemana](https://github.com/vemana) | | | | 00:02.902 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_spullara.java)| 21.0.1-graal | [Sam Pullara](https://github.com/spullara) | | | | 00:02.906 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_artsiomkorzun.java)| 21.0.1-graal | [artsiomkorzun](https://github.com/artsiomkorzun) | | | | 00:02.970 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_isolgpus.java)| 21.0.1-open | [Jamie Stansfield](https://github.com/isolgpus) | | * Tune chunksize to get another 2% improvement for 8 processors as used by the evaluation script. * Read int at a time for city name length detection; speeds up by 2% in local testing. * Improve reading temperature double by exiting loop quicker; no major tricks (like reading an int) yet, but good for 5th place on leaderboard in local testing. This small change has caused a surprising gain in performance by about 4%. I didn't expect such a big change, but perhaps in combination with the earlier change to read int by int for the city name, temperature reading is dominating that aspect of the time. Also, perhaps the quicker exit (as soon as you see '.' instead of reading until '\n') means you get to simply skip reading the '\n' across each of the lines. Since the lines are on average like 15 characters, it may be that avoiding reading the \n is a meaningful saving. Or maybe the JIT found a clever optimization for reading the temperature. Or maybe it is simply the case that the number of multiplications is now down to 2 from the previous 3 is what's causing the performance gain? | # | Result (m:s.ms) | Implementation | JDK | Submitter | Notes | |---|-----------------|--------------------|-----|---------------|-----------| | 1 | 00:01.531 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thomaswue.java)| 21.0.1-graal | [Thomas Wuerthinger](https://github.com/thomaswue) | GraalVM native binary | | 2 | 00:01.794 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java)| 21.0.1-graal | [Roy van Rijn](https://github.com/royvanrijn) | | | 3 | 00:01.956 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_merykitty.java)| 21.0.1-open | [Quan Anh Mai](https://github.com/merykitty) | | | | 00:02.346 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ebarlas.java)| 21.0.1-graal | [Elliot Barlas](https://github.com/ebarlas) | | | | 00:02.673 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_vemana.java)| 21.0.1-graal | [Subrahmanyam](https://github.com/vemana) | | | | 00:02.689 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_obourgain.java)| 21.0.1-open | [Olivier Bourgain](https://github.com/obourgain) | | | | 00:02.785 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_algirdasrascius.java)| 21.0.1-open | [Algirdas Ra__ius](https://github.com/algirdasrascius) | | | | 00:02.926 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_isolgpus.java)| 21.0.1-open | [Jamie Stansfield](https://github.com/isolgpus) | | | | 00:02.928 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_artsiomkorzun.java)| 21.0.1-graal | [Artsiom Korzun](https://github.com/artsiomkorzun) | | | | 00:02.932 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_spullara.java)| 21.0.1-graal | [Sam Pullara](https://github.com/spullara) | | * Reduce one multiplication when temperature is +ve. * Linear probe for city indexing. Beats current leader spullara 2.2 vs 3.8 elapsed time. * Straightforward impl using bytebuffers. Turns out memorysegments were slower than used mappedbytebuffers. * A initial submit-worthy entry Comparison to select entries (averaged over 3 runs) * spullara 1.66s [5th on leaderboard currently] * vemana (this submission) 1.65s * artsiomkorzun 1.64s [4th on leaderboard currently] Tests: PASS Impl Class: dev.morling.onebrc.CalculateAverage_vemana Machine specs * 16 core Ryzen 7950X * 128GB RAM Description * Decompose the full file into Shards of memory mapped files and process each independently, outputting a TreeMap: City -> Statistics * Compose the final answer by merging the individual TreeMap outputs * Select 1 Thread per available processor as reported by the JVM * Size to fit all datastructure in 0.5x L3 cache (4MB/core on the evaluation machines) * Use linear probing hash table, with identity of city name = byte[] and hash code computed inline * Avoid all allocation in the hot path and instead use method parameters. So, instead of passing a single Object param called Point(x, y, z), pass 3 parameters for each of its components. It is ugly, but this challenge is so far from Java's idioms anyway * G1GC seems to want to interfere; use ParallelGC instead (just a quick and dirty hack) Things tried that did not work * MemorySegments are actually slower than MappedByteBuffers * Trying to inline everything: not needed; the JIT compiler is pretty good * Playing with JIT compiler flags didn't yield clear wins. In particular, was surprised that using a max level of 3 and reducing compilation threshold did nothing.. when the jit logs print that none of the methods reach level 4 and stay there for long * Hand-coded implementation of Array.equals(..) using readLong(..) & bitmask_based_on_length from a bytebuffer instead of byte by byte * Further tuning to compile loop methods: timings are now consistenctly ahead of artsiomkorzun in 4th place. There are methods on the data path that were being interpreted for far too long. For example, the method that takes a byte range and simply calls one method per line was taking a disproportionate amount of time. Using `-XX:+AlwaysCompileLoopMethods` option improved completion time by 4%. ============= vemana =============== [20:55:22] [lsv@vemana]$ for i in 1 2 3 4 5; do ./runTheir.sh vemana; done; Using java version 21.0.1-graal in this shell. real 0m1.581s user 0m34.166s sys 0m1.435s Using java version 21.0.1-graal in this shell. real 0m1.593s user 0m34.629s sys 0m1.470s Using java version 21.0.1-graal in this shell. real 0m1.632s user 0m35.893s sys 0m1.340s Using java version 21.0.1-graal in this shell. real 0m1.596s user 0m33.074s sys 0m1.386s Using java version 21.0.1-graal in this shell. real 0m1.611s user 0m35.516s sys 0m1.438s ============= artsiomkorzun =============== [20:56:12] [lsv@vemana]$ for i in 1 2 3 4 5; do ./runTheir.sh artsiomkorzun; done; Using java version 21.0.1-graal in this shell. real 0m1.669s user 0m38.043s sys 0m1.287s Using java version 21.0.1-graal in this shell. real 0m1.679s user 0m37.840s sys 0m1.400s Using java version 21.0.1-graal in this shell. real 0m1.657s user 0m37.607s sys 0m1.298s Using java version 21.0.1-graal in this shell. real 0m1.643s user 0m36.852s sys 0m1.392s Using java version 21.0.1-graal in this shell. real 0m1.644s user 0m36.951s sys 0m1.279s ============= spullara =============== [20:57:55] [lsv@vemana]$ for i in 1 2 3 4 5; do ./runTheir.sh spullara; done; Using java version 21.0.1-graal in this shell. real 0m1.676s user 0m37.404s sys 0m1.386s Using java version 21.0.1-graal in this shell. real 0m1.652s user 0m36.509s sys 0m1.486s Using java version 21.0.1-graal in this shell. real 0m1.665s user 0m36.451s sys 0m1.506s Using java version 21.0.1-graal in this shell. real 0m1.671s user 0m36.917s sys 0m1.371s Using java version 21.0.1-graal in this shell. real 0m1.634s user 0m35.624s sys 0m1.573s ========================== Running Tests ====================== [21:17:57] [lsv@vemana]$ ./runTests.sh vemana Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10000-unique-keys.txt Using java version 21.0.1-graal in this shell. real 0m0.150s user 0m1.035s sys 0m0.117s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10.txt Using java version 21.0.1-graal in this shell. real 0m0.114s user 0m0.789s sys 0m0.116s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-1.txt Using java version 21.0.1-graal in this shell. real 0m0.115s user 0m0.948s sys 0m0.075s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-20.txt Using java version 21.0.1-graal in this shell. real 0m0.113s user 0m0.926s sys 0m0.066s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-2.txt Using java version 21.0.1-graal in this shell. real 0m0.110s user 0m0.734s sys 0m0.078s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-3.txt Using java version 21.0.1-graal in this shell. real 0m0.114s user 0m0.870s sys 0m0.095s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-boundaries.txt Using java version 21.0.1-graal in this shell. real 0m0.113s user 0m0.843s sys 0m0.084s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-complex-utf8.txt Using java version 21.0.1-graal in this shell. real 0m0.121s user 0m0.852s sys 0m0.171s * Improve by a few % more; now, convincingly faster than 6th place submission. So far, only algorithms and tuning; no bitwise tricks yet. Improve chunking implementation to avoid allocation and allow finegrained chunking for the last X% of work. Work now proceeds in two stages: big chunk stage and small chunk stage. This is to avoid straggler threads holding up result merging. Tests pass [07:14:49] [lsv@vemana]$ ./test.sh vemana Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10000-unique-keys.txt Using java version 21.0.1-graal in this shell. real 0m0.152s user 0m0.973s sys 0m0.107s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-10.txt Using java version 21.0.1-graal in this shell. real 0m0.113s user 0m0.840s sys 0m0.060s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-1.txt Using java version 21.0.1-graal in this shell. real 0m0.107s user 0m0.681s sys 0m0.085s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-20.txt Using java version 21.0.1-graal in this shell. real 0m0.105s user 0m0.894s sys 0m0.068s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-2.txt Using java version 21.0.1-graal in this shell. real 0m0.099s user 0m0.895s sys 0m0.068s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-3.txt Using java version 21.0.1-graal in this shell. real 0m0.098s user 0m0.813s sys 0m0.050s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-boundaries.txt Using java version 21.0.1-graal in this shell. real 0m0.095s user 0m0.777s sys 0m0.087s Validating calculate_average_vemana.sh -- src/test/resources/samples/measurements-complex-utf8.txt Using java version 21.0.1-graal in this shell. real 0m0.112s user 0m0.904s sys 0m0.069s * Merge results from finished threads instead of waiting for all threads to finish. Not a huge difference overall but no reason to wait. Also experiment with a few other compiler flags and attempt to use jitwatch to understand what the jit is doing. * Move to prepare_*.sh format and run evaluate2.sh locally. Shows 7th place in leaderboard | # | Result (m:s.ms) | Implementation | JDK | Submitter | Notes | |---|-----------------|--------------------|-----|---------------|-----------| | 1 | 00:01.588 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thomaswue.java)| 21.0.1-graal | [Thomas Wuerthinger](https://github.com/thomaswue) | GraalVM native binary | | 2 | 00:01.866 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_merykitty.java)| 21.0.1-open | [Quan Anh Mai](https://github.com/merykitty) | | | 3 | 00:01.904 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java)| 21.0.1-graal | [Roy van Rijn](https://github.com/royvanrijn) | | | | 00:02.398 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ebarlas.java)| 21.0.1-graal | [Elliot Barlas](https://github.com/ebarlas) | | | | 00:02.724 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_obourgain.java)| 21.0.1-open | [Olivier Bourgain](https://github.com/obourgain) | | | | 00:02.771 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_algirdasrascius.java)| 21.0.1-open | [Algirdas Ra__ius](https://github.com/algirdasrascius) | | | | 00:02.842 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_vemana.java)| 21.0.1-graal | [Vemana](https://github.com/vemana) | | | | 00:02.902 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_spullara.java)| 21.0.1-graal | [Sam Pullara](https://github.com/spullara) | | | | 00:02.906 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_artsiomkorzun.java)| 21.0.1-graal | [artsiomkorzun](https://github.com/artsiomkorzun) | | | | 00:02.970 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_isolgpus.java)| 21.0.1-open | [Jamie Stansfield](https://github.com/isolgpus) | | * Tune chunksize to get another 2% improvement for 8 processors as used by the evaluation script. * Read int at a time for city name length detection; speeds up by 2% in local testing. * Improve reading temperature double by exiting loop quicker; no major tricks (like reading an int) yet, but good for 5th place on leaderboard in local testing. This small change has caused a surprising gain in performance by about 4%. I didn't expect such a big change, but perhaps in combination with the earlier change to read int by int for the city name, temperature reading is dominating that aspect of the time. Also, perhaps the quicker exit (as soon as you see '.' instead of reading until '\n') means you get to simply skip reading the '\n' across each of the lines. Since the lines are on average like 15 characters, it may be that avoiding reading the \n is a meaningful saving. Or maybe the JIT found a clever optimization for reading the temperature. Or maybe it is simply the case that the number of multiplications is now down to 2 from the previous 3 is what's causing the performance gain? | # | Result (m:s.ms) | Implementation | JDK | Submitter | Notes | |---|-----------------|--------------------|-----|---------------|-----------| | 1 | 00:01.531 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_thomaswue.java)| 21.0.1-graal | [Thomas Wuerthinger](https://github.com/thomaswue) | GraalVM native binary | | 2 | 00:01.794 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_royvanrijn.java)| 21.0.1-graal | [Roy van Rijn](https://github.com/royvanrijn) | | | 3 | 00:01.956 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_merykitty.java)| 21.0.1-open | [Quan Anh Mai](https://github.com/merykitty) | | | | 00:02.346 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_ebarlas.java)| 21.0.1-graal | [Elliot Barlas](https://github.com/ebarlas) | | | | 00:02.673 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_vemana.java)| 21.0.1-graal | [Subrahmanyam](https://github.com/vemana) | | | | 00:02.689 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_obourgain.java)| 21.0.1-open | [Olivier Bourgain](https://github.com/obourgain) | | | | 00:02.785 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_algirdasrascius.java)| 21.0.1-open | [Algirdas Ra__ius](https://github.com/algirdasrascius) | | | | 00:02.926 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_isolgpus.java)| 21.0.1-open | [Jamie Stansfield](https://github.com/isolgpus) | | | | 00:02.928 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_artsiomkorzun.java)| 21.0.1-graal | [Artsiom Korzun](https://github.com/artsiomkorzun) | | | | 00:02.932 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_spullara.java)| 21.0.1-graal | [Sam Pullara](https://github.com/spullara) | | * Reduce one multiplication when temperature is +ve. * Added some documentation on the approach. --------- Co-authored-by: vemana <vemana.github@gmail.com> |
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Gunnar Morling
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209e005461 | Leaderboard, clean-up | ||
Jason Nochlin
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c92c88b9fb
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evaluate2.sh improvements - leaderboard, default SDK
* reset the JDK to the default (21.0.1-open) when no prepare script is provided * leaderboard improvements - sorting and content * run sdk install once at the beginning of the script for all the SDKs detected in any of the evaluated prepare scripts * remove unnecessary code and tweak doc comments * one more nit * Don't print rankings values when only 1 fork is being evaluated * It's been a few hours, so I now have some more rate limit :) --------- Co-authored-by: Jason Nochlin <hundredwatt@users.noreply.github.com> |