RFR: 8243389: enhance os::pd_print_cpu_info on linux

[Doerr, Martin]

Hi Matthias,

I'd use ExtensiveErrorReports for cache related info and the following ones:
"Maximum cpu frequency:"
"Minimum cpu frequency:"
"Current cpu frequency:"
"Available governors:"

Thanks and best regards,
Martin


> -----Original Message-----
> From: Baesken, Matthias <matthias.baesken at sap.com>
> Sent: Dienstag, 28. April 2020 12:53
> To: Doerr, Martin <martin.doerr at sap.com>; 'hotspot-
> dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> Subject: RE: RFR: 8243389: enhance os::pd_print_cpu_info on linux
> 
> > "Maximum cpu frequency" and "Minimum cpu frequency:" seems to be
> redundant when we have "Available cpu frequencies:".
> 
> Hi Martin, I added  all those intentionally because different  kernels/setups
> might report one but not the other.
> 
> > Please consider using ExtensiveErrorReports for some information like e.g.
> cache related info.
> 
> Good point, we should take this into consideration.
> Maybe some other opinions ? I would then guard the cache and frequency
> related info with the flag (or would you like to keep the frequency related
> info by default) ?
> 
> 
> Best regards, Matthias
> 
> -----Original Message-----
> From: Doerr, Martin <martin.doerr at sap.com>
> Sent: Dienstag, 28. April 2020 12:27
> To: Baesken, Matthias <matthias.baesken at sap.com>; 'hotspot-
> dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> Subject: RE: RFR: 8243389: enhance os::pd_print_cpu_info on linux
> 
> Hi Matthias,
> 
> technically, this looks good to me.
> 
> "Maximum cpu frequency" and "Minimum cpu frequency:" seems to be
> redundant when we have "Available cpu frequencies:".
> 
> I think it exceeds what a typical supporter needs to know in order to analyze
> issues.
> Please consider using ExtensiveErrorReports for some information like e.g.
> cache related info.
> 
> Best regards,
> Martin
> 
> 
> > -----Original Message-----
> > From: hotspot-dev <hotspot-dev-bounces at openjdk.java.net> On Behalf
> Of
> > Baesken, Matthias
> > Sent: Dienstag, 28. April 2020 11:45
> > To: 'hotspot-dev at openjdk.java.net' <hotspot-dev at openjdk.java.net>
> > Subject: RE: RFR: 8243389: enhance os::pd_print_cpu_info on linux
> >
> > Ping ... any reviews please?
> >
> > Thanks, Matthias
> >
> > -------------------------------
> > Hello, please review the following enhancement of  os::pd_print_cpu_info
> > on linux .
> > It adds  information about
> > cache
> > online/offline cpus
> > frequency details
> > governors
> >
> > by looking at the info provided at /sys/devices/system/cpu  .
> >
> > .....
> > bug/webrev :
> >
> > https://bugs.openjdk.java.net/browse/JDK-8243389
> >
> > http://cr.openjdk.java.net/~mbaesken/webrevs/8243389.0/