Reduce overhead by ByteBufUtil.decodeString(...) which is used by AbstractByteBuf.toString(...) and AbstractByteBuf.getCharSequence(...) (#8388)
Motivation:
Our current implementation that is used for toString(Charset) operations on AbstractByteBuf implementation is quite slow as it does a lot of uncessary memory copies. We should just use new String(...) as it has a lot of optimizations to handle these cases.
Modifications:
Rewrite ByteBufUtil.decodeString(...) to use new String(...)
Result:
Less overhead for toString(Charset) operations.
Benchmark (charsetName) (direct) (size) Mode Cnt Score Error Units
ByteBufUtilDecodeStringBenchmark.decodeString US-ASCII false 8 thrpt 20 22401645.093 ? 4671452.479 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString US-ASCII false 64 thrpt 20 23678483.384 ? 3749164.446 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString US-ASCII true 8 thrpt 20 15731142.651 ? 3782931.591 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString US-ASCII true 64 thrpt 20 16244232.229 ? 1886259.658 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-8 false 8 thrpt 20 25983680.959 ? 5045782.289 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-8 false 64 thrpt 20 26235589.339 ? 2867004.950 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-8 true 8 thrpt 20 18499027.808 ? 4784684.268 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-8 true 64 thrpt 20 16825286.141 ? 1008712.342 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-16 false 8 thrpt 20 5789879.092 ? 1201786.359 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-16 false 64 thrpt 20 2173243.225 ? 417809.341 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-16 true 8 thrpt 20 5035583.011 ? 1001978.854 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString UTF-16 true 64 thrpt 20 2162345.301 ? 402410.408 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString ISO-8859-1 false 8 thrpt 20 30039052.376 ? 6539111.622 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString ISO-8859-1 false 64 thrpt 20 31414163.515 ? 2096710.526 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString ISO-8859-1 true 8 thrpt 20 19538587.855 ? 4639115.572 ops/s
ByteBufUtilDecodeStringBenchmark.decodeString ISO-8859-1 true 64 thrpt 20 19467839.722 ? 1672687.213 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld US-ASCII false 8 thrpt 20 10787326.745 ? 1034197.864 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld US-ASCII false 64 thrpt 20 7129801.930 ? 1363019.209 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld US-ASCII true 8 thrpt 20 9002529.605 ? 2017642.445 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld US-ASCII true 64 thrpt 20 3860192.352 ? 826218.738 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-8 false 8 thrpt 20 10532838.027 ? 2151743.968 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-8 false 64 thrpt 20 7185554.597 ? 1387685.785 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-8 true 8 thrpt 20 7352253.316 ? 1333823.850 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-8 true 64 thrpt 20 2825578.707 ? 349701.156 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-16 false 8 thrpt 20 7277446.665 ? 1447034.346 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-16 false 64 thrpt 20 2445929.579 ? 562816.641 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-16 true 8 thrpt 20 6201174.401 ? 1236137.786 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld UTF-16 true 64 thrpt 20 2310674.973 ? 525587.959 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld ISO-8859-1 false 8 thrpt 20 11142625.392 ? 1680556.468 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld ISO-8859-1 false 64 thrpt 20 8127116.405 ? 1128513.860 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld ISO-8859-1 true 8 thrpt 20 9405751.952 ? 2193324.806 ops/s
ByteBufUtilDecodeStringBenchmark.decodeStringOld ISO-8859-1 true 64 thrpt 20 3943282.076 ? 737798.070 ops/s
Benchmark result is saved to /home/norman/mainframer/netty/microbench/target/reports/performance/ByteBufUtilDecodeStringBenchmark.json
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1,030.173 sec - in io.netty.buffer.ByteBufUtilDecodeStringBenchmark
[1030.460s][info ][gc,heap,exit ] Heap
[1030.460s][info ][gc,heap,exit ] garbage-first heap total 516096K, used 257918K [0x0000000609a00000, 0x0000000800000000)
[1030.460s][info ][gc,heap,exit ] region size 2048K, 127 young (260096K), 2 survivors (4096K)
[1030.460s][info ][gc,heap,exit ] Metaspace used 17123K, capacity 17438K, committed 17792K, reserved 1064960K
[1030.460s][info ][gc,heap,exit ] class space used 1709K, capacity 1827K, committed 1920K, reserved 1048576K
87ec2f882a