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Posted to users@cloudstack.apache.org by Len Bellemore <Le...@ControlCircle.com> on 2013/07/23 19:06:26 UTC

storage overprovisioning

Hi Guys,

Was wondering if someone could explain to me the difference between the following Global Settings:

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

Many thanks!
Len

________________________________
IMPORTANT NOTICE. This electronic message contains information from Control Circle Ltd, which may be privileged or confidential. The information is intended for use only by the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is strictly prohibited. If you have received this electronic message in error, please notify me by telephone or email (to the number or email address above) immediately. Activity and use of the ControlCircle e-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system will also be monitored and may be recorded to secure effective operation and for other lawful business purposes

RE: storage overprovisioning

Posted by Geoff Higginbottom <ge...@shapeblue.com>.
Hi Len,

The only problem with your approach is that if your users created a bunch of 1TB Data Volumes (the default maximum) but put next to no data on them, with overprovisioning set to 1, the system will assume they all have 1TB of data allocated and it could mark the storage as full and prevent its use, even though it has massive amounts of free space.

Regards

Geoff Higginbottom

D: +44 20 3603 0542 | S: +44 20 3603 0540 | M: +447968161581

geoff.higginbottom@shapeblue.com

-----Original Message-----
From: Len Bellemore [mailto:Len.Bellemore@ControlCircle.com]
Sent: 24 July 2013 13:48
To: users@cloudstack.apache.org
Subject: RE: storage overprovisioning

Hi Geoff,

That's a really great explanation. Thanks.

One option then is to still use thin provisioning on  the storage array, but not put in any kind of overprovisioning factor in Cloudstack.  We could then give ourselves a fairly large volume on the array, and defer the monitoring of "real" used space to storage monitoring tools.  This would take away the confusion around how storage is displayed in the Cloudstack UI, as it would be displaying "actual" space available, and it would take away any guess work around by which factor I should be overprovisioning in Cloudstack.

I would still see the benefits of thin provisioning to my array as a whole, but what is actually available to my Cloudstack users would be a lot more clearly defined.   I would not have CS administrators looking at the display in the UI and thinking, "well it says I've got 200GB available, but how much have I really got"

Len



-----Original Message-----
From: Geoff Higginbottom [mailto:geoff.higginbottom@shapeblue.com]
Sent: 24 July 2013 09:23
To: users@cloudstack.apache.org
Subject: RE: storage overprovisioning

Hi Len,

Some Background:

There are two Storage 'measures', the actual storage 'used', and the storage 'allocated'.

As an example let's assume you are using NFS, have 100GB of Primary Storage, and have set storage.overprovisioning.factor to 4

Because of the Over Provisioning Factor, your system will report that you have 0GB / 400GB of Primary Storage 'Allocated' and 0GB /100GB 'used'

If you now deploy 5 VMs, based on a Template with a 10GB ROOT disk, your 'allocated' storage would now be reporting as 50GB / 400GB of Primary Storage Allocated or 12.5%

However, due to the wonders of Thin Provisioning, the ROOT disks for each of the VMs are only currently using 2GB of actual storage, so your 'used' Storage will be reported as 10GB / 100GB or 10 %

Now as the VMs get used, data gets added, updates installed etc, the thin provisioned disks will grow, and may now be consuming 6GB of disk space each, and so the 'used' Storage will now be reported as 30GB / 100GB or 35% but the 'allocated' will still be 12.5%

As a Service Provider, the 'Allocated' setting is what you bill your clients for, as they have effectively reserved this amount of space, but you need to monitor the 'allocated' to make sure it does get too close to your limits.  But from an IT management perspective it's the 'used' Storage amount, which is the real data on disk value which may be more important as this will tell you when you disks are about to fill up.

The two Global Settings you originally asked about

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

They simply prevent any more Volumes from being allocated to the Primary Storage when the disable threshold is exceeded, and is measured as a percentage, with 85% expressed as 0.85

They allow you to decide which counter will disable the allocation of new Volumes, 'Allocated' or 'Used'

Regards

Geoff Higginbottom

D: +44 20 3603 0542 | S: +44 20 3603 0540 | M: +447968161581

geoff.higginbottom@shapeblue.com

-----Original Message-----
From: Len Bellemore [mailto:Len.Bellemore@ControlCircle.com]
Sent: 23 July 2013 18:06
To: users@cloudstack.apache.org
Subject: storage overprovisioning

Hi Guys,

Was wondering if someone could explain to me the difference between the following Global Settings:

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

Many thanks!
Len

________________________________
IMPORTANT NOTICE. This electronic message contains information from Control Circle Ltd, which may be privileged or confidential. The information is intended for use only by the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is strictly prohibited. If you have received this electronic message in error, please notify me by telephone or email (to the number or email address above) immediately. Activity and use of the ControlCircle e-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system will also be monitored and may be recorded to secure effective operation and for other lawful business purposes This email and any attachments to it may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Shape Blue Ltd or related companies. If you are not the intended recipient of this email, you must neither take any action based upon its contents, nor copy or show it to anyone. Please contact the sender if you believe you have received this email in error. Shape Blue Ltd is a company incorporated in England & Wales. ShapeBlue Services India LLP is operated under license from Shape Blue Ltd. ShapeBlue is a registered trademark.

________________________________
IMPORTANT NOTICE. This electronic message contains information from Control Circle Ltd, which may be privileged or confidential. The information is intended for use only by the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is strictly prohibited. If you have received this electronic message in error, please notify me by telephone or email (to the number or email address above) immediately. Activity and use of the ControlCircle e-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system will also be monitored and may be recorded to secure effective operation and for other lawful business purposes
This email and any attachments to it may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Shape Blue Ltd or related companies. If you are not the intended recipient of this email, you must neither take any action based upon its contents, nor copy or show it to anyone. Please contact the sender if you believe you have received this email in error. Shape Blue Ltd is a company incorporated in England & Wales. ShapeBlue Services India LLP is operated under license from Shape Blue Ltd. ShapeBlue is a registered trademark.

RE: storage overprovisioning

Posted by Len Bellemore <Le...@ControlCircle.com>.
Hi Geoff,

That's a really great explanation. Thanks.

One option then is to still use thin provisioning on  the storage array, but not put in any kind of overprovisioning factor in Cloudstack.  We could then give ourselves a fairly large volume on the array, and defer the monitoring of "real" used space to storage monitoring tools.  This would take away the confusion around how storage is displayed in the Cloudstack UI, as it would be displaying "actual" space available, and it would take away any guess work around by which factor I should be overprovisioning in Cloudstack.

I would still see the benefits of thin provisioning to my array as a whole, but what is actually available to my Cloudstack users would be a lot more clearly defined.   I would not have CS administrators looking at the display in the UI and thinking, "well it says I've got 200GB available, but how much have I really got"

Len



-----Original Message-----
From: Geoff Higginbottom [mailto:geoff.higginbottom@shapeblue.com]
Sent: 24 July 2013 09:23
To: users@cloudstack.apache.org
Subject: RE: storage overprovisioning

Hi Len,

Some Background:

There are two Storage 'measures', the actual storage 'used', and the storage 'allocated'.

As an example let's assume you are using NFS, have 100GB of Primary Storage, and have set storage.overprovisioning.factor to 4

Because of the Over Provisioning Factor, your system will report that you have 0GB / 400GB of Primary Storage 'Allocated' and 0GB /100GB 'used'

If you now deploy 5 VMs, based on a Template with a 10GB ROOT disk, your 'allocated' storage would now be reporting as 50GB / 400GB of Primary Storage Allocated or 12.5%

However, due to the wonders of Thin Provisioning, the ROOT disks for each of the VMs are only currently using 2GB of actual storage, so your 'used' Storage will be reported as 10GB / 100GB or 10 %

Now as the VMs get used, data gets added, updates installed etc, the thin provisioned disks will grow, and may now be consuming 6GB of disk space each, and so the 'used' Storage will now be reported as 30GB / 100GB or 35% but the 'allocated' will still be 12.5%

As a Service Provider, the 'Allocated' setting is what you bill your clients for, as they have effectively reserved this amount of space, but you need to monitor the 'allocated' to make sure it does get too close to your limits.  But from an IT management perspective it's the 'used' Storage amount, which is the real data on disk value which may be more important as this will tell you when you disks are about to fill up.

The two Global Settings you originally asked about

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

They simply prevent any more Volumes from being allocated to the Primary Storage when the disable threshold is exceeded, and is measured as a percentage, with 85% expressed as 0.85

They allow you to decide which counter will disable the allocation of new Volumes, 'Allocated' or 'Used'

Regards

Geoff Higginbottom

D: +44 20 3603 0542 | S: +44 20 3603 0540 | M: +447968161581

geoff.higginbottom@shapeblue.com

-----Original Message-----
From: Len Bellemore [mailto:Len.Bellemore@ControlCircle.com]
Sent: 23 July 2013 18:06
To: users@cloudstack.apache.org
Subject: storage overprovisioning

Hi Guys,

Was wondering if someone could explain to me the difference between the following Global Settings:

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

Many thanks!
Len

________________________________
IMPORTANT NOTICE. This electronic message contains information from Control Circle Ltd, which may be privileged or confidential. The information is intended for use only by the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is strictly prohibited. If you have received this electronic message in error, please notify me by telephone or email (to the number or email address above) immediately. Activity and use of the ControlCircle e-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system will also be monitored and may be recorded to secure effective operation and for other lawful business purposes This email and any attachments to it may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Shape Blue Ltd or related companies. If you are not the intended recipient of this email, you must neither take any action based upon its contents, nor copy or show it to anyone. Please contact the sender if you believe you have received this email in error. Shape Blue Ltd is a company incorporated in England & Wales. ShapeBlue Services India LLP is operated under license from Shape Blue Ltd. ShapeBlue is a registered trademark.

________________________________
IMPORTANT NOTICE. This electronic message contains information from Control Circle Ltd, which may be privileged or confidential. The information is intended for use only by the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is strictly prohibited. If you have received this electronic message in error, please notify me by telephone or email (to the number or email address above) immediately. Activity and use of the ControlCircle e-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system will also be monitored and may be recorded to secure effective operation and for other lawful business purposes

RE: storage overprovisioning

Posted by Geoff Higginbottom <ge...@shapeblue.com>.
Hi Len,

Some Background:

There are two Storage 'measures', the actual storage 'used', and the storage 'allocated'.

As an example let's assume you are using NFS, have 100GB of Primary Storage, and have set storage.overprovisioning.factor to 4

Because of the Over Provisioning Factor, your system will report that you have 0GB / 400GB of Primary Storage 'Allocated' and 0GB /100GB 'used'

If you now deploy 5 VMs, based on a Template with a 10GB ROOT disk, your 'allocated' storage would now be reporting as 50GB / 400GB of Primary Storage Allocated or 12.5%

However, due to the wonders of Thin Provisioning, the ROOT disks for each of the VMs are only currently using 2GB of actual storage, so your 'used' Storage will be reported as 10GB / 100GB or 10 %

Now as the VMs get used, data gets added, updates installed etc, the thin provisioned disks will grow, and may now be consuming 6GB of disk space each, and so the 'used' Storage will now be reported as 30GB / 100GB or 35% but the 'allocated' will still be 12.5%

As a Service Provider, the 'Allocated' setting is what you bill your clients for, as they have effectively reserved this amount of space, but you need to monitor the 'allocated' to make sure it does get too close to your limits.  But from an IT management perspective it's the 'used' Storage amount, which is the real data on disk value which may be more important as this will tell you when you disks are about to fill up.

The two Global Settings you originally asked about

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

They simply prevent any more Volumes from being allocated to the Primary Storage when the disable threshold is exceeded, and is measured as a percentage, with 85% expressed as 0.85

They allow you to decide which counter will disable the allocation of new Volumes, 'Allocated' or 'Used'

Regards

Geoff Higginbottom

D: +44 20 3603 0542 | S: +44 20 3603 0540 | M: +447968161581

geoff.higginbottom@shapeblue.com

-----Original Message-----
From: Len Bellemore [mailto:Len.Bellemore@ControlCircle.com]
Sent: 23 July 2013 18:06
To: users@cloudstack.apache.org
Subject: storage overprovisioning

Hi Guys,

Was wondering if someone could explain to me the difference between the following Global Settings:

pool.storage.allocated.capacity.disablethreshold
pool.storage.capacity.disablethreshold

Many thanks!
Len

________________________________
IMPORTANT NOTICE. This electronic message contains information from Control Circle Ltd, which may be privileged or confidential. The information is intended for use only by the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this information is strictly prohibited. If you have received this electronic message in error, please notify me by telephone or email (to the number or email address above) immediately. Activity and use of the ControlCircle e-mail system is monitored to secure its effective operation and for other lawful business purposes. Communications using this system will also be monitored and may be recorded to secure effective operation and for other lawful business purposes
This email and any attachments to it may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Shape Blue Ltd or related companies. If you are not the intended recipient of this email, you must neither take any action based upon its contents, nor copy or show it to anyone. Please contact the sender if you believe you have received this email in error. Shape Blue Ltd is a company incorporated in England & Wales. ShapeBlue Services India LLP is operated under license from Shape Blue Ltd. ShapeBlue is a registered trademark.