Do not read a JAR completely into a byte-array before computing the SHA

[jvdvegt]

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[olamy]

Looks like a very good improvement! Thanks!
I wonder if you could mention this in this documentation page https://maven.apache.org/extensions/maven-build-cache-extension/performance.html

[jvdvegt]

Looks like a very good improvement! Thanks! I wonder if you could mention this in this documentation page https://maven.apache.org/extensions/maven-build-cache-extension/performance.html

Yes, will do!

Update @olamy : is this really the source for the docs? An SVN-repo? https://svn.apache.org/repos/asf/maven/website/components/extensions/maven-build-cache-extension/performance.html

That has been a while! How do I get access? I'd like to add a paragraph right after the 'General notes' part:

Supported hash algorithms

The following hash algorithms are supported:

• METRO
• SHA1
• SHA256
• SHA384
• SHA512
• XX

All algorithms come in two flavors: the default one, which fully reads artifacts in memory, and a 'memory mapped' version, which reduces memory requirements but needs additional --add-opens on JDK >= 17 (see below). The memory mapped version of an algorithm has a _MM postfix added to the algorithm name, e..g SHA1_MM (note that as an exception, XXMM has no underscore in its name).

To use the Memory Mapped versions to algorithms, the file .mvn/jvm.config needs to be present in the top directory of your project with the following line to run successfully on JDK >= 17.

--add-opens java.base/sun.nio.ch=ALL-UNNAMED

Hash algorithm selection

By default, the cache uses the XX algorithm, which is a very fast hash algorithm and should be enough for most use cases. In projects with a large codebase, the performance of hash algorithms becomes more critical, and other algorithms like XXMM (XX with memory-mapped files) could provide better performance, depending on the environment.

<hashAlgorithm>XX</hashAlgorithm>

Filter out unnecessary artifacts

[olamy]

@jvdvegt the sources for the page are in the repo https://github.com/apache/maven-build-cache-extension/blob/master/src/site/markdown/performance.md

[olamy]

@jvdvegt thanks for your hard. I fixed test in master. can you just rebase, we get a last green build and this will be merged

[jvdvegt]

@olamy : I think I rebased it (I'm not very familiar with GitHub multi-repos). Thanks for reviewing this!

[olamy]

@jvdvegt all merged. Thanks for your contribution! (and patience :) )