[RFR] 8202427: Enhance os::print_memory_info on Windows

[Baesken, Matthias]

Ping :   could I get a second review ?

Bug :
https://bugs.openjdk.java.net/browse/JDK-8202427
Change :
http://cr.openjdk.java.net/~mbaesken/webrevs/8202427.0/


> We could also  just print  the  MB  value  , let's see what other think.
> Another option might be to have a flexible output   (kB for  smaller  memory
> values , MB   (or GB)  for larger ) ?

Martin suggested to just print  the  MB values,   what do you think ?


Thanks, Matthias


> -----Original Message-----
> From: Baesken, Matthias
> Sent: Mittwoch, 2. Mai 2018 13:00
> To: Doerr, Martin <martin.doerr at sap.com>; 'hotspot-
> dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>; hotspot-
> runtime-dev at openjdk.java.net
> Subject: RE: [RFR] 8202427: Enhance os::print_memory_info on Windows
> 
> Hi Martin,  thanks for your input .
> I add  hotspot-runtime-dev  .
> 
> >
> > I wonder if we really need the sizes in kB in addition to MB. Maybe other
> > reviewers would like to comment on this, too.
> >
> 
> We could also  just print  the  MB  value  , let's see what other think.
> Another option might be to have a flexible output   (kB for  smaller  memory
> values , MB   (or GB)  for larger ) ?
> 
> Best regards, Matthias
> 
> 
> > -----Original Message-----
> > From: Doerr, Martin
> > Sent: Mittwoch, 2. Mai 2018 12:53
> > To: Baesken, Matthias <matthias.baesken at sap.com>; 'hotspot-
> > dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> > Subject: RE: [RFR] 8202427: Enhance os::print_memory_info on Windows
> >
> > Hi Matthias,
> >
> > looks like a nice enhancement. We can get substantially more information.
> >
> > I wonder if we really need the sizes in kB in addition to MB. Maybe other
> > reviewers would like to comment on this, too.
> >
> > We should have line breaks.
> >
> > Best regards,
> > Martin
> >
> >
> > -----Original Message-----
> > From: hotspot-dev [mailto:hotspot-dev-bounces at openjdk.java.net] On
> > Behalf Of Baesken, Matthias
> > Sent: Montag, 30. April 2018 16:53
> > To: 'hotspot-dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> > Subject: [RFR] 8202427: Enhance os::print_memory_info on Windows
> >
> > On Windows,
> > the os::print_memory_info  misses a few  memory-related infos that might
> > be interesting :
> > - current and peak WorkingSet size  (= physical memory assigned to the
> > process)
> > - current and peak commit charge  (also known as "private bytes" in
> Windows
> > tools)
> > - on 32bit Windows :
> > user-mode portion/free user mode portion  of virtual address-space
> > (Total/AvailVirtual) because it shows how close do we get to the 2-4 GB per
> > process border.
> >
> >
> > - the current naming of "swap/free-swap" memory is a bit misleading;
> > in the Windows world swap is a special page file used for UWP apps.
> > (see Windows Internals :  "The swap file"  (chapter 5 Memory
> management)
> > Windows 8 added another page file called a swap file. It is ... exclusively
> used
> > for UWP (Universal Windows Platform) apps.
> > Our output (ullTotalPageFile and ullAvailPageFile) is NOT about the UWP
> > related values, it is about page file sizes
> > (so calling it TotalPageFile/AvailPageFile in "Windows-speak" or just virtual
> > memory might be more appropriate).
> >
> >
> > https://msdn.microsoft.com/de-
> > de/library/windows/desktop/aa366770(v=vs.85).aspx
> >
> > documents it in the following way:
> > ullTotalPageFile:
> > The current committed memory limit for the system or the current process,
> > whichever is smaller,...
> >
> > ullAvailPageFile :
> > The maximum amount of memory the current process can commit, in
> bytes.
> > This value is equal to or smaller than the system-wide available commit
> value
> >
> >
> >
> > Aditionally I suggest having output of the various memory-values  in M
> > (megabyte) as well , the k  (kilobyte) output sometimes gives very high and
> > unreadable numbers).
> >
> >
> > Could you please  review my change ?
> >
> >
> > Bug :
> >
> > https://bugs.openjdk.java.net/browse/JDK-8202427
> >
> >
> > Change :
> >
> > http://cr.openjdk.java.net/~mbaesken/webrevs/8202427.0/
> >
> >
> > Thanks, Matthias
> >