[cfarm-users] Nice on GCC202?

[Anatoly Pugachev]

On Fri, Mar 9, 2018 at 11:04 AM, Baptiste Jonglez via cfarm-users
<cfarm-users at lists.tetaneutral.net> wrote:
> On 08-03-18, Jeffrey Walton wrote:
>> On Thu, Mar 8, 2018 at 6:19 PM, Baptiste Jonglez
>> <baptiste at bitsofnetworks.org> wrote:
>> > Hi,
>> >
>> > On 08-03-18, Jeffrey Walton via cfarm-users wrote:
>> >> Hi Everyone,
>> >>
>> >> GCC202 is a Sparc64 machine. It has 16 cpus and each cpu has 16 cores
>> >> for a total of 256 virtual cpu's.
>> >
>> > Where did you see those 256 "virtual cpu's"?  According to htop,
>> > /proc/cpuinfo and https://cfarm.tetaneutral.net/machines/list/ it only has
>> > 16 "threads".
>>
>> /sys/devices/system/cpu
>>
>> Related, do you know where the CPU freq is tucked away on Sparc64? It
>> is not in the places I usually look, like /proc/cpuinfo and
>> /sys/devices/system/cpu.
>
> To kill two birds with one stone:
>
> $ cat /sys/devices/system/cpu/cpu*/clock_tick | uniq -c
>      16 3599910000
>
> So, only 16 threads, each at 3.6 GHz.

Just to clarify things, gcc202 is LDOM [1] (read virtual machine),
running on a SPARC T5-2 server [2], which has 2x CPU sparc T5 [3].
gcc202 is allocated only 2 cores (out of 32 cores (2 cpus) in physical
server), so it's 16 threads in total:

sysadmin at deimos:~$ ldm list cfgcc
NAME             STATE      FLAGS   CONS    VCPU  MEMORY   UTIL  NORM  UPTIME
cfgcc            active     -n----  5003    16    8G       6.5%  6.5%  9d 20h 6m

I could probably add 1 more core (8 more threads), if someone really
needs it and/or building big projects which will actually use more
threads.

And ping me, if it will need more RAM, still have some available.

So, if you run parallel make, please consider to use 3/4 of total
threads (depends on a time your project building, if it will complete
in a short amount of time, use 3/4 of total threads, if it runs longer
take just a half of available threads).

Thanks!

1. https://en.wikipedia.org/wiki/Oracle_VM_Server_for_SPARC
2. http://www.oracle.com/us/products/servers-storage/servers/sparc/oracle-sparc/t5-2/sparc-t5-2-ds-1922871.pdf
3. https://en.wikipedia.org/wiki/SPARC_T5