YAML Processor leaves StreamDecoder open [SPR-13173]

[spring-projects-issues]

Erik Salter opened SPR-13173 and commented

When the YAMLProcessor is closed, it is still leaving a reference to a StreamDecoder instance open. (See UnicodeReader::init()) While Spring’s YamlProcessor closes the underlying input stream, the StreamDecoder (and thus the reference to the YAML and all its loaded references) remain open until the YAML reference is eventually GC’d.

The issue comes in when these references are promoted from new to the old generation. The references are then only collected on a FGC. In the interim, the application can have many open handles (we counted 900+ on a production system that only had 2 FGC cycles)

Attached is a snapshot after the YAMLProcessor closes the stream.

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Affects: 4.1.3

Reference URL: #17093

Attachments:

• yaml.png (70.46 kB)

Issue Links:

• Need a defensive close() in YamlProcessor [SPR-12487] #17093 Need a defensive close() in YamlProcessor

Referenced from: commits 26acb48, 3d131c9

[spring-projects-issues]

Juergen Hoeller commented

It looks like we'll have to avoid the Yaml.load(InputStream) method altogether, using a loadFromReader call with a custom UnicodeReader handle which we're able to close afterwards...

This is arguably a bug in that Yaml class itself. However, if we can work around so easily, let's try to do that.

Juergen