Re: RFR: 8264777: Overload optimized FileInputStream::readAllBytes [v8]
On Mon, 17 May 2021 17:00:15 GMT, Brian Burkhalter wrote:
>> Please consider this request to override the `java.io.InputStream` methods
>> `readAllBytes()` and `readNBytes(int)` in `FileInputStream` with more
>> performant implementations. The method overrides attempt to read all
>> requested bytes into a single array of the required size rather than
>> composing the result from a sequence of smaller arrays. An example of the
>> performance improvements is as follows.
>>
>> **readAllBytes**
>> Before
>>
>> Benchmark(length) Mode Cnt Score
>> Error Units
>> ReadAllBytes.readAllBytesFileInputStream 100 thrpt 20 2412.031
>> ± 7.309 ops/s
>> ReadAllBytes.readAllBytesFileInputStream 1000 thrpt 20212.181
>> ± 0.369 ops/s
>> ReadAllBytes.readAllBytesFileInputStream1 thrpt 20 19.860
>> ± 0.048 ops/s
>> ReadAllBytes.readAllBytesFileInputStream 10 thrpt 20 1.298
>> ± 0.183 ops/s
>>
>> After
>>
>> Benchmark(length) Mode Cnt Score
>> Error Units
>> ReadAllBytes.readAllBytesFileInputStream 100 thrpt 20 8218.473
>> ± 43.425 ops/s
>> ReadAllBytes.readAllBytesFileInputStream 1000 thrpt 20302.781
>> ± 1.273 ops/s
>> ReadAllBytes.readAllBytesFileInputStream1 thrpt 20 22.461
>> ± 0.084 ops/s
>> ReadAllBytes.readAllBytesFileInputStream 10 thrpt 20 1.502
>> ± 0.003 ops/s
>>
>>
>> **readNBytes**
>>
>> `N = file_size / 2`
>>
>> Before
>>
>> Benchmark(length) Mode Cnt Score
>> Error Units
>> ReadAllBytes.readHalfBytesFileInputStream 100 thrpt 20 5585.500
>> ± 153.353 ops/s
>> ReadAllBytes.readHalfBytesFileInputStream1000 thrpt 20436.164
>> ± 1.104 ops/s
>> ReadAllBytes.readHalfBytesFileInputStream 1 thrpt 20 40.167
>> ± 0.141 ops/s
>> ReadAllBytes.readHalfBytesFileInputStream 10 thrpt 20 3.291
>> ± 0.211 ops/s
>>
>>
>> After
>>
>> Benchmark(length) Mode Cnt Score
>> Error Units
>> ReadAllBytes.readHalfBytesFileInputStream 100 thrpt 20 15463.210
>> ± 66.045 ops/s
>> ReadAllBytes.readHalfBytesFileInputStream1000 thrpt 20561.752
>> ± 0.951 ops/s
>> ReadAllBytes.readHalfBytesFileInputStream 1 thrpt 20 45.043
>> ± 0.102 ops/s
>> ReadAllBytes.readHalfBytesFileInputStream 10 thrpt 20 4.629
>> ± 0.035 ops/s
>
> Brian Burkhalter has updated the pull request incrementally with one
> additional commit since the last revision:
>
> 8264777: Clean up test
Marked as reviewed by alanb (Reviewer).
test/jdk/java/io/FileInputStream/ReadXBytes.java line 69:
> 67:
> 68: try (FileInputStream fis = new FileInputStream(empty)) {
> 69: byte[] b = fis.readAllBytes();
You could move this readAllBytes test up to the previous block if you want.
-
PR: https://git.openjdk.java.net/jdk/pull/3845
Re: RFR: 8264777: Overload optimized FileInputStream::readAllBytes [v8]
> Please consider this request to override the `java.io.InputStream` methods > `readAllBytes()` and `readNBytes(int)` in `FileInputStream` with more > performant implementations. The method overrides attempt to read all > requested bytes into a single array of the required size rather than > composing the result from a sequence of smaller arrays. An example of the > performance improvements is as follows. > > **readAllBytes** > Before > > Benchmark(length) Mode Cnt Score >Error Units > ReadAllBytes.readAllBytesFileInputStream 100 thrpt 20 2412.031 > ± 7.309 ops/s > ReadAllBytes.readAllBytesFileInputStream 1000 thrpt 20212.181 > ± 0.369 ops/s > ReadAllBytes.readAllBytesFileInputStream1 thrpt 20 19.860 > ± 0.048 ops/s > ReadAllBytes.readAllBytesFileInputStream 10 thrpt 20 1.298 > ± 0.183 ops/s > > After > > Benchmark(length) Mode Cnt Score >Error Units > ReadAllBytes.readAllBytesFileInputStream 100 thrpt 20 8218.473 > ± 43.425 ops/s > ReadAllBytes.readAllBytesFileInputStream 1000 thrpt 20302.781 > ± 1.273 ops/s > ReadAllBytes.readAllBytesFileInputStream1 thrpt 20 22.461 > ± 0.084 ops/s > ReadAllBytes.readAllBytesFileInputStream 10 thrpt 20 1.502 > ± 0.003 ops/s > > > **readNBytes** > > `N = file_size / 2` > > Before > > Benchmark(length) Mode Cnt Score >Error Units > ReadAllBytes.readHalfBytesFileInputStream 100 thrpt 20 5585.500 > ± 153.353 ops/s > ReadAllBytes.readHalfBytesFileInputStream1000 thrpt 20436.164 > ± 1.104 ops/s > ReadAllBytes.readHalfBytesFileInputStream 1 thrpt 20 40.167 > ± 0.141 ops/s > ReadAllBytes.readHalfBytesFileInputStream 10 thrpt 20 3.291 > ± 0.211 ops/s > > > After > > Benchmark(length) Mode Cnt Score >Error Units > ReadAllBytes.readHalfBytesFileInputStream 100 thrpt 20 15463.210 > ± 66.045 ops/s > ReadAllBytes.readHalfBytesFileInputStream1000 thrpt 20561.752 > ± 0.951 ops/s > ReadAllBytes.readHalfBytesFileInputStream 1 thrpt 20 45.043 > ± 0.102 ops/s > ReadAllBytes.readHalfBytesFileInputStream 10 thrpt 20 4.629 > ± 0.035 ops/s Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision: 8264777: Clean up test - Changes: - all: https://git.openjdk.java.net/jdk/pull/3845/files - new: https://git.openjdk.java.net/jdk/pull/3845/files/4fae0209..17e21c9a Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3845&range=07 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3845&range=06-07 Stats: 49 lines in 1 file changed: 6 ins; 3 del; 40 mod Patch: https://git.openjdk.java.net/jdk/pull/3845.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/3845/head:pull/3845 PR: https://git.openjdk.java.net/jdk/pull/3845
