RFR: JDK-8282382: Report glibc malloc tunables in error reports

[Thomas Stuefe]

On Fri, 25 Feb 2022 14:05:03 GMT, Zhengyu Gu <zgu at openjdk.org> wrote:

>> On Linux/glibc platforms, the hs-err file should report the malloc tunables, or at least MALLOC_ARENA_MAX, since that one can have a significant effect on footprint or malloc contention for a VM.
>> 
>> This patch adds this printout as a one-liner into hs-err files and jcmd VM.info reports:
>> 
>> 
>> Process Memory:                                                                    
>> ...
>> glibc malloc tunables: MALLOC_PERTURB_=40, MALLOC_ARENA_MAX=1
>> 
>> 
>> If the tunables are default, we print `glibc malloc tunables: (default)`.
>> 
>> 
>> Thanks, Thomas
>
> src/hotspot/os/linux/os_linux.cpp line 2169:
> 
>> 2167: #endif // __GLIBC__
>> 2168: 
>> 2169: #ifdef __GLIBC__
> 
> You can merge these two `#ifdef __GLIBC__` blocks.

Will do.

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PR: https://git.openjdk.java.net/jdk/pull/7620