RFR: 8240824: enhance print_full_memory_info on Linux by THP related information

[Baesken, Matthias]

Thanks. May I have a second review ?

Best Regards, Matthias


From: Thomas Stüfe <thomas.stuefe at gmail.com>
Sent: Donnerstag, 12. März 2020 14:33
To: Baesken, Matthias <matthias.baesken at sap.com>
Cc: hotspot-dev at openjdk.java.net
Subject: Re: RFR: 8240824: enhance print_full_memory_info on Linux by THP related information

Hi Matthias,

too verbose for my taste:


+  st->print_cr("/sys/kernel/mm/transparent_hugepage/enabled (transparent huge pages mode):");

I would cut that down to either "/sys/kernel/mm/transparent_hugepage/enabled" or to "transparent huge pages mode". Probably the former.

Otherwise looks good. I do not need a new webrev.

Cheers, Thomas



On Tue, Mar 10, 2020 at 4:09 PM Baesken, Matthias <matthias.baesken at sap.com<mailto:matthias.baesken at sap.com>> wrote:
Hello, please review this small enhancement .

On Linux, the change adds output of some files related to THP (transparent huge pages)   configuration to the hs_err file; the settings in those files configure how transparent huge pages are used on the system.

Example output in the hs_err file from a test machine :


/sys/kernel/mm/transparent_hugepage/enabled (transparent huge pages mode):
[always] madvise never

/sys/kernel/mm/transparent_hugepage/defrag (defrag/compaction efforts parameter):
[always] madvise never




Bug/webrev :

https://bugs.openjdk.java.net/browse/JDK-8240824

http://cr.openjdk.java.net/~mbaesken/webrevs/8240824.0/


Thanks, Matthias