Possible working method to get actual process size on Linux

[Per Liden]

Yes, 3 times.

/Per

On 10/3/19 3:15 PM, Stefan Reich wrote:
> So ZGC maps the heap 3 times, not 4?
> 
> I realize this is not a good assumption to rely on, but I still like to 
> know...
> 
> On Thu, 3 Oct 2019 at 15:06, Per Liden <per.liden at oracle.com 
> <mailto:per.liden at oracle.com>> wrote:
> 
> 
>     On 10/3/19 2:52 PM, Stefan Reich wrote:
>      > Breakdown of the process's pages by RSS:
>      >
>      > Address range 000000xxxxxxxxxx: 1 MB
>      > Address range 000004xxxxxxxxxx: 2461 MB
>      > Address range 000008xxxxxxxxxx: 2476 MB
>      > Address range 000010xxxxxxxxxx: 2662 MB
>      > Address range 00007cxxxxxxxxxx: 648 MB
>      >
>      > This is really getting confusing...
> 
>     You have three Java heap mappings (~2.5G) + non-Java heap stuff (648M),
>     which gives you ~3.1G, which is similar to what ps_mem reports.
> 
>     /Per
> 
>      >
>      > On Thu, 3 Oct 2019 at 14:47, Stefan Reich
>      > <stefan.reich.maker.of.eye at googlemail.com
>     <mailto:stefan.reich.maker.of.eye at googlemail.com>
>      > <mailto:stefan.reich.maker.of.eye at googlemail.com
>     <mailto:stefan.reich.maker.of.eye at googlemail.com>>> wrote:
>      >
>      >     The situation is still confusing. My process has:
>      >
>      >     Runtime.totalMemory() = 2.7 GB
>      >     Runtime.usedMemory() =~ 1 GB
>      >
>      >     ps_mem.py says:
>      >
>      >     root at smartbot:~/bin# ps_mem.py -p 4837
>      >       Private  +   Shared  =  RAM used Program
>      >
>      >     745.5 MiB +   2.4 GiB =   3.1 GiB java
>      >     ---------------------------------
>      >                                3.1 GiB
>      >
>      >     Is the heap counted as shared memory here? The shared memory
>     value
>      >     seems way too large.
>      >
>      >     My own tool reports < 1 GB as RSS which seems way too low...
>      >
>      >
>      >     On Thu, 3 Oct 2019 at 14:32, Per Liden <per.liden at oracle.com
>     <mailto:per.liden at oracle.com>
>      >     <mailto:per.liden at oracle.com <mailto:per.liden at oracle.com>>>
>     wrote:
>      >
>      >
>      >         On 10/3/19 2:23 PM, Stefan Reich wrote:
>      >          > Hi Per!
>      >          >
>      >          > Yes, I saw, sorry for not responding the other time.
>      >          >
>      >          > This problem is, /proc/*/smaps_rollup doesn't exist on
>     one of my
>      >          > machines (the one with the oldest kernel). On the newer
>      >         machines, yeah,
>      >          > it may be an option to use PSS from smaps_rollup.
>      >          >
>      >          > Not sure if there are any tools which would help here.
>      >
>      >         I know some of them (e.g. ps_mem.py), works on older
>     kernels that
>      >         doesn't have /proc/<pid>/smaps_rollup.
>      >
>      >         cheers,
>      >         Per
>      >
>      >          >
>      >          > Greetings,
>      >          > Stefan
>      >          >
>      >          > On Thu, 3 Oct 2019 at 14:16, Per Liden
>     <per.liden at oracle.com <mailto:per.liden at oracle.com>
>      >         <mailto:per.liden at oracle.com <mailto:per.liden at oracle.com>>
>      >          > <mailto:per.liden at oracle.com
>     <mailto:per.liden at oracle.com> <mailto:per.liden at oracle.com
>     <mailto:per.liden at oracle.com>>>>
>      >         wrote:
>      >          >
>      >          >
>      >          >     Did you see my reply to your previous question on this
>      >         topic? Tools to
>      >          >     extract this data (PSS) exist. Are they not doing what
>      >         you want?
>      >          >
>      >          >     cheers,
>      >          >     Per
>      >          >
>      >          >
>      >          >
>      >          > --
>      >          > Stefan Reich
>      >          > BotCompany.de // Java-based operating systems
>      >
>      >
>      >
>      >     --
>      >     Stefan Reich
>      >     BotCompany.de // Java-based operating systems
>      >
>      >
>      >
>      > --
>      > Stefan Reich
>      > BotCompany.de // Java-based operating systems
> 
> 
> 
> -- 
> Stefan Reich
> BotCompany.de // Java-based operating systems