Avoid extra byte copy inside FileSystemImpl.readFileInternal#5730
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@franz1981 please take a look |
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@vietj PTAL I added a test with JMH. Here are the results on my machine. Latency
The advantage grows with file size. At 1 MB, Allocations per operation
From 4 KB up, At 128 B the gap is smaller, probably because of the fixed overhead (FileChannel/Path objects, ByteBuf header) dominates over the data copy. |
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Jun 19, 2026
Closes eclipse-vertx#5677 The improvement consists in creating the buffer upfront and using Netty API to read the file channel. Signed-off-by: Thomas Segismont <tsegismont@gmail.com>
On my machine, the advantage grows with file size. At 1MB, using the Netty FileChannel method is nearly 2x faster and allocates half as much as the Files.readAllBytes approach. Signed-off-by: Thomas Segismont <tsegismont@gmail.com>
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…6213) * Avoid extra byte copy inside FileSystemImpl.readFileInternal Closes #5677 The improvement consists in creating the buffer upfront and using Netty API to read the file channel. * Added ReadFileBenchmark On my machine, the advantage grows with file size. At 1MB, using the Netty FileChannel method is nearly 2x faster and allocates half as much as the Files.readAllBytes approach. --------- Signed-off-by: Thomas Segismont <tsegismont@gmail.com>
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See #5665
The improvement consists in creating the buffer upfront and using Netty API to read the file channel.