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root disk quota for project

asked 2017-04-28 09:18:42 -0500

Damian Dąbrowski gravatar image


Is there any way to set root disk quota(GB) for project? I can see only option for creating cinder volume quota :/

I would be grateful for any help.

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It doesn't look like it. Indirectly: Set quota on the number of instances. Combined with the flavors available to that project the total amount of ephemeral storage is effectively limited.

Bernd Bausch gravatar imageBernd Bausch ( 2017-04-28 19:46:20 -0500 )edit


Ok, Thank You Bernd.

So if you understand it correctly, the formula is:

project_max_ephemeral_storage_size = max_number_of_instances * ephemeral_disk_size_in_biggest_available_flavor

and there is no way to set this limit directly?

Damian Dąbrowski gravatar imageDamian Dąbrowski ( 2017-04-30 10:03:47 -0500 )edit

I made this formula up, but yes, I would think it's correct. And there is no direct way to limit ephemeral storage.

Let me also point you to the quotas section in the Operations Guide.

Bernd Bausch gravatar imageBernd Bausch ( 2017-05-01 07:00:17 -0500 )edit

Ok, Thank You!

Damian Dąbrowski gravatar imageDamian Dąbrowski ( 2017-05-05 05:16:35 -0500 )edit

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answered 2018-07-06 06:29:30 -0500

gadamiak gravatar image

I'm guessing you want to set a total storage quota for volumes and ephemeral. Using only cinder quota doens't give that control as project user may use lots of storage using big flavors. To account for that you need do subtract maximum estimated ephemeral storage usage from the total storage quota you want the project to consume to get cinder quota. To calculate it you might use the following formula:

cinder_quota = total_storage_quota − total_cpu_quota / flavor_min_cpu × flavor_total_disk

For example with 120GB total storage quota and 4 vCPUs

  • flavor of 1 vCPU and 10GB total storage

    cinder_quota = 120GB - 4 vCPU/1 vCPU × 10GB = 80GB
  • flavor of 2 vCPU and 40GB total storage

    cinder_quota = 120GB - 4 vCPU/2 vCPU × 40GB = 40GB
  • flavor of 4 vCPU and 60GB total storage

    cinder_quota = 120GB - 4 vCPU/4 vCPU × 60GB = 60GB
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Asked: 2017-04-28 09:18:42 -0500

Seen: 220 times

Last updated: Jul 06