RFR: 8295320: [BACKOUT] 8276687 Remove support for JDK 1.4.1 PerfData shared memory files

[Ioi Lam]

On Fri, 14 Oct 2022 09:53:23 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

> Hi, are you sure you want to back this out? I'll click approve as backout change I think looks OK.
> 
> I see test/hotspot/jtreg/serviceability/dcmd/framework/VMVersionTest.java failing SOMETIMES for me. I think you already noted that src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/protocol/local/PerfDataBuffer.java no longer handles IllegalArgumentException
> 
> If we handle that then for me the test that failed frequently, runs OK 20 times in a row.
> 
> ```
> bash-4.2$ git diff
> diff --git a/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/protocol/local/PerfDataBuffer.java b/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/protocol/local/PerfDataBuffer.java
> index 3ad35e350e4..056671d7841 100644
> --- a/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/protocol/local/PerfDataBuffer.java
> +++ b/src/jdk.internal.jvmstat/share/classes/sun/jvmstat/perfdata/monitor/protocol/local/PerfDataBuffer.java
> @@ -63,7 +63,7 @@ public class PerfDataBuffer extends AbstractPerfDataBuffer {
>          try {
>              ByteBuffer bb = perf.attach(vmid.getLocalVmId());
>              createPerfDataBuffer(bb, vmid.getLocalVmId());
> -        } catch (IOException e) {
> +        } catch (IOException | IllegalArgumentException e) {
>              throw new MonitorException("Could not attach to "
>                                         + vmid.getLocalVmId(), e);
>          }
> ```

I want to do more testing and then make a REDO PR for the 1.4.1 code removal. I also want to understand why these tests would sometimes get an IllegalArgumentException.

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PR: https://git.openjdk.org/jdk/pull/10711