RFR: 8359706: Add file descriptor count and maximum limit to VM.info [v6]

[Kieran Farrell]

On Mon, 19 Jan 2026 17:31:10 GMT, Kevin Walls <kevinw at openjdk.org> wrote:

>> Kieran Farrell has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 23 commits:
>> 
>>  - Merge branch 'openjdk:master' into JDK_8359706
>>  - comment
>>  - timed loop for aix and linux proc read
>>  - rm unused variables
>>  - updates
>>  - clean up
>>  - clean up
>>  - undo commit to linux.cpp
>>  - rm max count and malloc
>>  - bsd.cpp
>>  - ... and 13 more: https://git.openjdk.org/jdk/compare/1342db0b...1f34d255
>
> Hi - Could you include an example of what this looks like in context, an excerpt from the whole output showing the new info in context?
> 
> It's between "printing heap information" and "printing GC information", which might be a bit odd as those things should stay grouped together for humans to read?
> 
> Would it be a better fit in the "OS:" section which is where we show e.g. limit information.

Hi @kevinjwalls, here is a snippit from the current position under "PROCESS". I added it here since the count is process related but I agree it might be nice to have it closer to the NOFILE count int the "OS" section under "SYSTEM".


---------------  P R O C E S S  ---------------

Heap address: 0x0000000320000000, size: 9216 MB, Compressed Oops mode: Zero based, Oop shift amount: 3

CDS archive(s) not mapped
Compressed class space mapped at: 0x00000fc000000000-0x00000fc040000000, reserved size: 1073741824
UseCompressedClassPointers 1, UseCompactObjectHeaders 0
Narrow klass pointer bits 32, Max shift 3
Narrow klass base: 0x00000fc000000000, Narrow klass shift: 0
Encoding Range: [0x00000fc000000000 - 0x00000fc100000000), (4294967296 bytes)
Klass Range:    [0x00000fc000000000 - 0x00000fc040000000), (1073741824 bytes)
Klass ID Range:  [8 - 1073741817) (1073741809)
Protection zone: [0x00000fc000000000 - 0x00000fc000010000), (65536 bytes)

OpenFileDescriptorCount = 5

GC Precious Log:
 CardTable entry size: 512
 Card Set container configuration: InlinePtr #cards 4 size 8 Array Of Cards #cards 64 size 144 Howl #buckets 8 coarsen threshold 14745 Howl Bitmap #cards 2048 size 272 coarsen threshold 1843 Card regions per heap region 1 cards per card region 16384
 CPUs: 11 total, 11 available
 Memory: 36864M
 Large Page Support: Disabled
 NUMA Support: Disabled
 Compressed Oops: Enabled (Zero based)
 Heap Region Size: 8M
 Heap Min Capacity: 8M
 Heap Initial Capacity: 8M
 Heap Max Capacity: 9G
 Pre-touch: Disabled
 Parallel Workers: 9
 Concurrent Workers: 2
 Concurrent Refinement Workers: 9
 Periodic GC: Disabled

Heap:
 garbage-first heap   total reserved 9437184K, committed 8192K, used 4545K [0x0000000320000000, 0x0000000560000000)
  region size 8M, 1 eden (8M), 0 survivor (0M), 0 old (0M), 0 humongous (0M), 0 free (0M)

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PR Comment: https://git.openjdk.org/jdk/pull/27971#issuecomment-3770120194