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

Wed May 16 13:48:48 UTC 2018

Hi Matthias, 

I appreciate the additional information in the hs_err file.
Could you please add an example output (of the final version) to the bug description?

As Martin, I would like more line feeds, both in the code and the output.
Currently, the output in the hs_err file looks like this (where the first line is too long):
    Memory: 4k page, system-wide physical 16776692k [16383M] (8795032k [8588M] free), TotalPageFile size 49949460k [48778M] (AvailPageFile size 38942152k [38029M]), user-mode portion of virtual address-space 2097024k [2047M] (6940k [6M] free)
    current process WorkingSet (physical memory assigned to process): 991804k [968M], peak: 991804k [968M]

    current process commit charge ("private bytes"): 1523632k [1487M], peak: 1523632k [1487M] 

I also think that one number is enough. Adaptive numbers would be great.
I know about 
    src/hotspot/share/memory/metaspace/metaspaceCommon.hpp: print_human_readable_size()
for this, but this seems a bit hidden in metaspace.

I don't like usage of _M_IX86. Common in this file seems #ifndef _WIN64 for 32-bit windows
dependent code.  But don't care here.

Best regards,
  Goetz.

> -----Original Message-----
> From: hotspot-dev [mailto:hotspot-dev-bounces at openjdk.java.net] On
> Behalf Of Baesken, Matthias
> Sent: Mittwoch, 16. Mai 2018 15:13
> 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
> 
> 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
> > >