alibaba/arthas · error · IllegalArgumentException

vmtool interruptThread 需要指定线程 ID (threadId)

Error message

vmtool interruptThread 需要指定线程 ID (threadId)

What it means

For the interruptThread action, a valid positive threadId is required to identify which thread to interrupt. A null or non-positive threadId (<=0) is rejected because thread IDs are always positive in the JVM.

Source

Thrown at core/src/main/java/com/taobao/arthas/core/mcp/tool/function/jvm300/VMToolTool.java:82

        }

        if (ACTION_GET_INSTANCES.equals(normalizedAction)) {
            if (limit != null) {
                cmd.append(" --limit ").append(limit);
            }
            if (expandLevel != null && expandLevel > 0) {
                cmd.append(" -x ").append(expandLevel);
            }
            if (express != null && !express.trim().isEmpty()) {
                addParameter(cmd, "--express", express);
            }
        }

        if (ACTION_INTERRUPT_THREAD.equals(normalizedAction)) {
            if (threadId != null && threadId > 0) {
                cmd.append(" -t ").append(threadId);
            } else {
                throw new IllegalArgumentException("vmtool interruptThread 需要指定线程 ID (threadId)");
            }
        }

        return executeSync(toolContext, cmd.toString());
    }


}

View on GitHub (pinned to 21cf2e9ba5)

Solutions

1. Use the thread command or tool first to find the target thread's numeric ID.
2. Pass a strictly positive threadId value.
3. Ensure the thread still exists (it may have already terminated).

Example fix

// before
vmtool(action="interruptThread")
// after
// first run: thread  (to list threads and find nid/tid)
vmtool(action="interruptThread", threadId=42)

// Before calling vmtool interruptThread, validate threadId
if ("interruptThread".equals(action) && (threadId == null || threadId <= 0)) {
    throw new IllegalArgumentException("A positive threadId is required for interruptThread");
}

try {
    String result = vmtool(action, ..., threadId, ...);
} catch (IllegalArgumentException e) {
    if (e.getMessage().contains("threadId")) {
        // threadId was missing or non-positive
    }
}

When it happens

Trigger: Calling vmtool with action=interruptThread while omitting threadId, passing null, or passing a value <= 0.

Common situations: User forgets to look up the thread ID first; passes threadId=0; MCP client omits the field; user confuses thread name with numeric ID.

Related errors

• vmtool: action 参数不能为空
• vmtool ${normalizedAction} 需要指定类名 (className)
• actionArg is required when action=execute
• action is required
• classPattern is required for record operation

AI-assisted analysis of alibaba/arthas@21cf2e9ba5 (2026-08-14). Data as JSON: /api/errors/b48b1679acaa58f8. Report an issue: GitHub.