[Starlingx-discuss] Question - Using 1Gb mem pages

[Perez, Ricardo O]

Hi Michael, 

Thanks for your answer, I just forgot to put the computes information about memory configuration, here is the info:

Compute-0

   VM Pages
0   Reserved for Platform: 8000 MiB
Usable Total: 86387 MiB
Available: 84787 MiB
    4K Pages:
    Total: 230656
2M Hugepages:
    Total: 1271
    Available: 983
1G Hugepages:
    Total: 80
    Available: 80

1   Reserved for Platform: 2000 MiB
Usable Total: 93698 MiB
Available: 92674 MiB
    4K Pages:
    Total: 29696
2M Hugepages:
    Total: 5319
    Available: 5319
1G Hugepages:
    Total: 80
    Available: 80

***********************************
Compute-1
Processor
    Memory
    VM Pages
0   Reserved for Platform: 8000 MiB
Usable Total: 86504 MiB
Available: 84968 MiB
    4K Pages:
    Total: 0
2M Hugepages:
    Total: 1780
    Available: 1524
1G Hugepages:
    Total: 80
    Available: 80

1   Reserved for Platform: 2000 MiB
Usable Total: 93552 MiB
Available: 92528 MiB
    4K Pages:
    Total: 0
2M Hugepages:
    Total: 5304
    Available: 5304
1G Hugepages:
    Total: 80
    Available: 80

Am I missing something else to made use of 1G memory pages ? 

Thanks
-Richo

> -----Original Message-----
> From: Michel Thebeau [mailto:michel.thebeau at windriver.com]
> Sent: Friday, October 19, 2018 1:39 PM
> To: Perez, Ricardo O <ricardo.o.perez at intel.com>; starlingx-
> discuss at lists.starlingx.io
> Subject: Re: [Starlingx-discuss] Question - Using 1Gb mem pages
> 
> On 2018-10-19 1:45 p.m., Perez, Ricardo O wrote:
> > Hello,
> >
> > I'm trying to execute a test, which his goal is to made use of huge pages (2M /
> 1G) launching a VM.
> >
> > I have already verified the configuration of the controllers GRUB options and
> we have defined the variable hugepagesz=1G, however, inside the same
> parameters list, there is a "default_hugepagesz=2M". The default hugepagesz,
> has been modified to 1G, and the compute has been restarted with no issues.
> 
> 
> Hi Ricardo,
> 
> You wrote, "controllers GRUB options" then "the compute has been restarted
> with no issues".  Is there a GRUB option one can configure on the controller that
> is for the computes?  I don't remember seeing one. If you're actually changing
> /etc/default/grub, I doubt that's supported.
> I did not find a procedure for changing default_hugepagesz  on controllers or
> computes grub configuration.
> 
> It's supposed to be an option, for example through in horizon interface or
> 'system host-memory-modify'... but you didn't quote either of those.
> 
> 
> >
> > The flavor has been modified, with the following option: "
> hw:mem_page_size=104875"  (1G) page.
> 
> 
> Is "104875" a typo?  It looks a lot like 1024 * 1024 = 1048576, but not
> quite.
> 
> 
> M
> 
> 
> >
> > However when I launch a VM using the modified flavor it creates the VM, but if
> I check the field values of the VM using " openstack server show <vm_name>".
> I'm getting the following value for pgsize:
> > wrs-res:topology                    | node:0,   512MB, pgsize:2M, vcpus:0, pol:sha |
> >
> > So, seems like it's still taking the 2M pagesize instead of the 1G.
> >
> > What I have already tried is to:
> >
> > *        Change also the image metadata: hw:mem_page_size=large and also
> 104875. Result, VM launched successfully, but pgsize value still 2M.
> 
> There's the interesting "104875" again.
> 
> 
> > *        Leave the GRUB default values, and use modified flavor to
> hw:mem_page_size=104875, launch the VM with ERROR status.
> 
> 104875
> 
> > *        Leave the GRUB default values, and use modified flavor to
> hw:mem_page_size=2048, launch the VM with success, , pgsize value is 2M,
> which is expected, ok.
> >
> > *        Leave the GRUB default values, and use modified flavor to
> hw:mem_page_size=small launch the VM with success, , pgsize value is 4k,
> which is  expected, ok.
> >
> > *        Leave the GRUB default values, and use modified flavor to
> hw:mem_page_size=any launch the VM with success, , pgsize value is 2M, which
> is  expected, ok.
> >
> > Could be this an issue trying to use 1G mem pages or do I'm missing some
> other configuration parameter?
> >
> > Thanks in advance for your help
> >
> >
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