RFR(xxs): 8251257: NMT: jcmd VM.native_memory scale=1 crashes target VM

[Thomas Stüfe]

Hi David,

On Sat, Aug 8, 2020 at 2:32 PM David Holmes <david.holmes at oracle.com> wrote:

> Hi Thomas,
>
> Wouldn't a scale name of "b" be more appropriate given the acceptance of
> "scale=b"? It seems weird to me that scale=1 is even accepted in the
> first place.
>

I am not sure what you refer to, the added case in the switch construct? If
yes, this is the string of the unit NMT prints its numbers with. For byte
sizes, we normally omit the unit, so I do it here too.

If you object against the name of the scale as used in the scale argument,
that has been there before and changing it is not subject of the patch. I
just don't want the target VM to crash.


> And can you please add some information to the bug report.
>
>
Done. I thought subject + assert printout would be sufficient, sorry for
the brevity.


> Thanks,
> David
>

Thank you, Thomas


>
> On 8/08/2020 4:15 pm, Thomas Stüfe wrote:
> > Hi,
> >
> > may I have a second Review please?
> >
> > All tests at SAP went through successfully, as did the jdk-submit tests
> at
> > Oracle.
> >
> > Thanks!
> >
> > ..Thomas
> >
> > On Thu, Aug 6, 2020 at 5:07 PM Thomas Stüfe <thomas.stuefe at gmail.com>
> wrote:
> >
> >> Hi,
> >>
> >> very simple small fix.
> >>
> >> jcmd VM.native_memory allows for scale=1 to print exact byte values, but
> >> crashes when printing.
> >>
> >> JBS: https://bugs.openjdk.java.net/browse/JDK-8251257
> >> webrev:
> >>
> http://cr.openjdk.java.net/~stuefe/webrevs/8251257-nmt-scale-1-crash/webrev.00/webrev/
> >>
> >> Thanks, Thomas
> >>
>