RFR (XS) 8061467: Add UseLargePages to TestNUMAPageSize

[Thomas Schatzl]

Hi JC,

  the changeset had a wrong CR number (8061467), and so the change has
been pushed under that CR on Wednesday already.

I will figure out how to handle the original CR (8063110).

Thanks,
  Thomas

On Tue, 2018-08-14 at 20:20 -0700, JC Beyler wrote:
> Hi all,
> 
> Here is the webrev with all the reviewers added:
> http://cr.openjdk.java.net/~jcbeyler/8063110/webrev.03/
> 
> Let me know if I can/should do anything else for this webrev.
> 
> Thanks for all your help,
> Jc
> 
> On Mon, Aug 13, 2018 at 11:04 PM Per Liden <per.liden at oracle.com>
> wrote:
> > Hi,
> > 
> > On 08/13/2018 06:22 PM, JC Beyler wrote:
> > > Hi all,
> > > 
> > > I added Per's fix into the webrev:
> > > http://cr.openjdk.java.net/~jcbeyler/8063110/webrev.02/
> > > 
> > > (I also put you Thomas as reviewer, I was not sure Per wanted to
> > be put 
> > > as reviewer, let me know).
> > 
> > Sure, you can put me as reviewer.
> > 
> > /Per
> > 
> > > 
> > > Not sure if you wanted to wait or not to push it but at least
> > this 
> > > version would be the version that does not run with ZGC.
> > > 
> > > Thanks for your help,
> > > Jc
> > > 
> > > On Mon, Aug 13, 2018 at 5:54 AM Per Liden <per.liden at oracle.com 
> > > <mailto:per.liden at oracle.com>> wrote:
> > > 
> > >     On 08/13/2018 11:41 AM, Thomas Schatzl wrote:
> > >      > Hi,
> > >      >
> > >      >    while testing this patch before push it seems like the
> > problem
> > >     is ZGC
> > >      > which does not fall back to using small pages (which I did
> > not know).
> > >      >
> > >      >> [5.048s][error][gc,init] Not enough space available on
> > the backing
> > >      > filesystem to hold the current max
> > >      >> [5.048s][error][gc,init] Java heap size (128M).
> > Forcefully lowering
> > >      > max Java heap size to 0M (0%).
> > >      >> Error occurred during initialization of VM
> > >      >> java.lang.OutOfMemoryError: Java heap too small
> > >      >
> > >      > I will hold off pushing this before this issue has been
> > resolved
> > >     in one
> > >      > way or the other.
> > > 
> > >     UseNUMA is enabled by default in ZGC, so it's tested
> > frequently anyway.
> > >     I guess the easiest solution is to just not run this test
> > when ZGC is
> > >     enabled, something like this:
> > > 
> > >     diff --git a/test/hotspot/jtreg/gc/TestNUMAPageSize.java
> > >     b/test/hotspot/jtreg/gc/TestNUMAPageSize.java
> > >     --- a/test/hotspot/jtreg/gc/TestNUMAPageSize.java
> > >     +++ b/test/hotspot/jtreg/gc/TestNUMAPageSize.java
> > >     @@ -27,7 +27,8 @@
> > >         * @summary Make sure that start up with NUMA support does
> > not cause
> > >     problems.
> > >         * @bug 8061467
> > >         * @requires vm.opt.AggressiveOpts != true
> > >     - * @run main/othervm -Xmx128m -XX:+UseNUMA TestNUMAPageSize
> > >     + * @requires vm.gc != "Z"
> > >     + * @run main/othervm -Xmx128m -XX:+UseNUMA
> > -XX:+UseLargePages
> > >     TestNUMAPageSize
> > >         */
> > > 
> > >        public class TestNUMAPageSize {
> > > 
> > > 
> > >     cheers,
> > >     Per
> > > 
> > > 
> > >      >
> > >      > Thanks,
> > >      >    Thomas
> > >      >
> > >      > On Mon, 2018-08-13 at 10:23 +0200, Thomas Schatzl wrote:
> > >      >> Hi,
> > >      >>
> > >      >> On Mon, 2018-08-13 at 09:58 +0200, Per Liden wrote:
> > >      >>> Hmm, I suspect this might fail on many Linux systems,
> > since it
> > >      >>> might require configuring the huge page pool with enough
> > pages.
> > >      >>
> > >      >>    from my understanding -XX:+UseLargePages will just
> > give some
> > >      >> warnings
> > >      >>   at startup if it can not allocate pages. It will not
> > fail.
> > >      >>
> > >      >> Assuming that the intent is to check whether when trying
> > to use
> > >     large
> > >      >> pages (and the machine is properly configured), does not
> > in any way
> > >      >> make the VM crash, the warnings can be ignored.
> > >      >>
> > >      >> I am not aware there is a way to run tests on machines
> > only that
> > >     have
> > >      >> the property "properly configured large pages" at this
> > time.
> > >      >>
> > >      >> Thanks,
> > >      >>    Thomas
> > >      >>
> > >      >
> > > 
> > > 
> > > 
> > > -- 
> > > 
> > > Thanks,
> > > Jc
> 
>