Yang LSP taking too much memory & stop working.

[Kaauw]

Hello Team,

I have an issue with Yang LSP (with Yangster vscode). It take too much memory and do not work.

Context

• VScode with remote ssh development.
• Workspace with 4 projects, each of them import the same yang base (Cisco NSO environment)

Versions

user@host:~$java --version
openjdk 11.0.25 2024-10-15
OpenJDK Runtime Environment (build 11.0.25+9-post-Ubuntu-1ubuntu122.04)
OpenJDK 64-Bit Server VM (build 11.0.25+9-post-Ubuntu-1ubuntu122.04, mixed mode, sharing)

user@host:~$uname -a
Linux ubuntu-server 5.15.0-125-generic #135-Ubuntu SMP Fri Sep 27 13:53:58 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

user@host:~$code --version
1.95.2
e8653663e8840adaf45af01eab5c627a5af81807
x64

CPU/Memory info

CPU/Memory after reboot and all services loaded, before opening a workspace :

Same output after workspace opened :

Problem

Yangster output there is an heap memory problem, and sometimes it crash for the whole workspace.

Troubleshooting done

Splitting workspaces

Not working as it pop a new Yang-LSP Process, this use all the VM Memory and make it not usable.

Increase the heap space

I saw in the server launch script I can change the heap space via two environment variables :

JAVA_OPTS= ??
YANG_LANGUAGE_SERVER_OPTS= ??

But I don't know Java & I don't know which value I can use here.

Output from vscode

[Info  - 1:27:32 PM] Indexing YangPath element: file:/var/opt/ncs/packages/private1/src/yang/private1.yang
[... 691 yangs files here ...]
[Info  - 1:28:37 PM] Indexing YangPath element: file:/opt/ncs/current/src/ncs/yang/tailf-ncs-kicker-extension.yang
[Error - 1:30:28 PM] Error loading yangPath resource class org.eclipse.emf.common.util.URI: java.lang.OutOfMemoryError: Java heap space
	at jdk.internal.reflect.GeneratedMethodAccessor5.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at org.eclipse.xtext.parser.antlr.AbstractInternalAntlrParser.parse(AbstractInternalAntlrParser.java:594)
	at org.eclipse.xtext.parser.antlr.AbstractAntlrParser.doParse(AbstractAntlrParser.java:103)
	at org.eclipse.xtext.parser.antlr.AbstractAntlrParser.parse(AbstractAntlrParser.java:85)
	at org.eclipse.xtext.parser.antlr.AbstractAntlrParser.doParse(AbstractAntlrParser.java:63)
	at org.eclipse.xtext.parser.AbstractParser.parse(AbstractParser.java:34)
	at org.eclipse.xtext.resource.XtextResource.doLoad(XtextResource.java:178)
	at org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLoad(LazyLinkingResource.java:115)
	at org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1563)
	at org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1342)
	at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoad(ResourceSetImpl.java:259)
	at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:274)
	at org.eclipse.xtext.resource.XtextResourceSet.getResource(XtextResourceSet.java:266)
	at org.eclipse.xtext.resource.SynchronizedXtextResourceSet.getResource(SynchronizedXtextResourceSet.java:33)
	at io.typefox.yang.utils.YangPathProvider.process(YangPathProvider.java:115)
	at io.typefox.yang.utils.YangPathProvider.lambda$process$3(YangPathProvider.java:109)
	at io.typefox.yang.utils.YangPathProvider$$Lambda$175/0x0000000840327440.accept(Unknown Source)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at io.typefox.yang.utils.YangPathProvider.process(YangPathProvider.java:111)
	at io.typefox.yang.utils.YangPathProvider.lambda$process$3(YangPathProvider.java:109)
	at io.typefox.yang.utils.YangPathProvider$$Lambda$175/0x0000000840327440.accept(Unknown Source)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at io.typefox.yang.utils.YangPathProvider.process(YangPathProvider.java:111)
	at io.typefox.yang.utils.YangPathProvider.lambda$process$3(YangPathProvider.java:109)
	at io.typefox.yang.utils.YangPathProvider$$Lambda$175/0x0000000840327440.accept(Unknown Source)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at io.typefox.yang.utils.YangPathProvider.process(YangPathProvider.java:111)
	at io.typefox.yang.utils.YangPathProvider.lambda$process$3(YangPathProvider.java:109)
	at io.typefox.yang.utils.YangPathProvider$$Lambda$175/0x0000000840327440.accept(Unknown Source)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)

Idea

1. Due to the fact that 4 projects import the same baseline, yang-lsp import recusively each base yang + service yang.
2. Splitting workspace into 4 workspaces is not a solution as it pop many processes and uses all the vm available memory.

Regards,

Ben