Hi,

is it any different way how to re-balance extents within storage pool in SVC  ?   

for example when a  new controller is added

I'm  still using balance.pl from (Scripting tools for SAN Volume Controller released  in 2013)  

surprisingly still accessible here :

https://www.ibm.com/resources/mrs/assets/DownloadList?source=swg-SVCTools&lang=en_US

thanks

Tomas

This is something that Easy Tier should be handling automatically.

So, the first question that I have is, do you have easy tier running on the storage pool in question?

------------------------------
Ian Wright IBM Champion for Storage, Red Hat Accelerator
System Engineer
Mainline Information Systems
IBM Champion for Storage
Red Hat Accelerator

Original Message:
Sent: Tue June 10, 2025 07:22 AM
From: Tomas Kovacik
Subject: SVC pool extents rebalancing

Hi,

is it any different way how to re-balance extents within storage pool in SVC  ?   

for example when a  new controller is added

I'm  still using balance.pl from (Scripting tools for SAN Volume Controller released  in 2013)  

surprisingly still accessible here :

https://www.ibm.com/resources/mrs/assets/DownloadList?source=swg-SVCTools&lang=en_US

thanks

Tomas

------------------------------
Tomas Kovacik
------------------------------

 based on what easy tier rebalance work ?

• free mdisk capacity
• mdisk io respons 
• both 

at the end i would like to have all mdisks equally occupied but it can't last half year 

------------------------------
Tomas Kovacik

Original Message:
Sent: Tue June 10, 2025 08:45 AM
From: Ian Wright
Subject: SVC pool extents rebalancing

This is something that Easy Tier should be handling automatically.

So, the first question that I have is, do you have easy tier running on the storage pool in question?

------------------------------
Ian Wright IBM Champion for Storage, Red Hat Accelerator
System Engineer
Mainline Information Systems
IBM Champion for Storage
Red Hat Accelerator

Original Message:
Sent: Tue June 10, 2025 07:22 AM
From: Tomas Kovacik
Subject: SVC pool extents rebalancing

Hi,

is it any different way how to re-balance extents within storage pool in SVC  ?   

for example when a  new controller is added

I'm  still using balance.pl from (Scripting tools for SAN Volume Controller released  in 2013)  

surprisingly still accessible here :

https://www.ibm.com/resources/mrs/assets/DownloadList?source=swg-SVCTools&lang=en_US

thanks

Tomas

------------------------------
Tomas Kovacik
------------------------------

Well, assuming that you're on a pretty current version of Storage Virtualize, it should be automatically enabled and should be balancing the extents across all of the mdisks in your pool. So, ideally you should have everything pretty balanced in the pool already.

The algorithm for this is based on work done by IBM research, but I don't know that anyone knows exactly how it works. But I believe it's mostly trying to balance out the performance across the volumes.

As for the speed, that's also something that is likely difficult to predict. It runs as a background process so that it doesn't interfere with your workload. But exactly how long is going to depend on how busy your system is and how fast the SAN is.

 based on what easy tier rebalance work ?

• free mdisk capacity
• mdisk io respons 
• both 

at the end i would like to have all mdisks equally occupied but it can't last half year 

------------------------------
Tomas Kovacik

Original Message:
Sent: Tue June 10, 2025 08:45 AM
From: Ian Wright
Subject: SVC pool extents rebalancing

This is something that Easy Tier should be handling automatically.

So, the first question that I have is, do you have easy tier running on the storage pool in question?

------------------------------
Ian Wright IBM Champion for Storage, Red Hat Accelerator
System Engineer
Mainline Information Systems
IBM Champion for Storage
Red Hat Accelerator

Original Message:
Sent: Tue June 10, 2025 07:22 AM
From: Tomas Kovacik
Subject: SVC pool extents rebalancing

Hi,

is it any different way how to re-balance extents within storage pool in SVC  ?   

for example when a  new controller is added

I'm  still using balance.pl from (Scripting tools for SAN Volume Controller released  in 2013)  

surprisingly still accessible here :

https://www.ibm.com/resources/mrs/assets/DownloadList?source=swg-SVCTools&lang=en_US

thanks

Tomas

------------------------------
Tomas Kovacik
------------------------------

i found this :

https://www.ibm.com/docs/en/flashsystem-9x00?topic=STSLR9/com.ibm.fs9200_841.doc/svc_easy_tier_acceleratedmode.htm

with easy_tier_acceleration on , migration rate is increased  from 12 GB per 5 minutes to 48 GB per 5 minutes 

9,6GB/min =  163 MB/s   , when i need to rebalance 1PB  ,  it will took 75  days 

my system can handle additional  load let's say 1GB/s  what would shorten migration to 12,5 days  or even half with 2GB/s

Well, assuming that you're on a pretty current version of Storage Virtualize, it should be automatically enabled and should be balancing the extents across all of the mdisks in your pool. So, ideally you should have everything pretty balanced in the pool already.

The algorithm for this is based on work done by IBM research, but I don't know that anyone knows exactly how it works. But I believe it's mostly trying to balance out the performance across the volumes.

As for the speed, that's also something that is likely difficult to predict. It runs as a background process so that it doesn't interfere with your workload. But exactly how long is going to depend on how busy your system is and how fast the SAN is.

 based on what easy tier rebalance work ?

• free mdisk capacity
• mdisk io respons 
• both 

at the end i would like to have all mdisks equally occupied but it can't last half year 

------------------------------
Tomas Kovacik

Original Message:
Sent: Tue June 10, 2025 08:45 AM
From: Ian Wright
Subject: SVC pool extents rebalancing

This is something that Easy Tier should be handling automatically.

So, the first question that I have is, do you have easy tier running on the storage pool in question?

------------------------------
Ian Wright IBM Champion for Storage, Red Hat Accelerator
System Engineer
Mainline Information Systems
IBM Champion for Storage
Red Hat Accelerator

Original Message:
Sent: Tue June 10, 2025 07:22 AM
From: Tomas Kovacik
Subject: SVC pool extents rebalancing

Hi,

is it any different way how to re-balance extents within storage pool in SVC  ?   

for example when a  new controller is added

I'm  still using balance.pl from (Scripting tools for SAN Volume Controller released  in 2013)  

surprisingly still accessible here :

https://www.ibm.com/resources/mrs/assets/DownloadList?source=swg-SVCTools&lang=en_US

thanks

Tomas

------------------------------
Tomas Kovacik
------------------------------

i found this :

https://www.ibm.com/docs/en/flashsystem-9x00?topic=STSLR9/com.ibm.fs9200_841.doc/svc_easy_tier_acceleratedmode.htm

with easy_tier_acceleration on , migration rate is increased  from 12 GB per 5 minutes to 48 GB per 5 minutes 

9,6GB/min =  163 MB/s   , when i need to rebalance 1PB  ,  it will took 75  days 

my system can handle additional  load let's say 1GB/s  what would shorten migration to 12,5 days  or even half with 2GB/s

Well, assuming that you're on a pretty current version of Storage Virtualize, it should be automatically enabled and should be balancing the extents across all of the mdisks in your pool. So, ideally you should have everything pretty balanced in the pool already.

The algorithm for this is based on work done by IBM research, but I don't know that anyone knows exactly how it works. But I believe it's mostly trying to balance out the performance across the volumes.

As for the speed, that's also something that is likely difficult to predict. It runs as a background process so that it doesn't interfere with your workload. But exactly how long is going to depend on how busy your system is and how fast the SAN is.

 based on what easy tier rebalance work ?

• free mdisk capacity
• mdisk io respons 
• both 

at the end i would like to have all mdisks equally occupied but it can't last half year 

------------------------------
Tomas Kovacik

Original Message:
Sent: Tue June 10, 2025 08:45 AM
From: Ian Wright
Subject: SVC pool extents rebalancing

This is something that Easy Tier should be handling automatically.

So, the first question that I have is, do you have easy tier running on the storage pool in question?

------------------------------
Ian Wright IBM Champion for Storage, Red Hat Accelerator
System Engineer
Mainline Information Systems
IBM Champion for Storage
Red Hat Accelerator

Original Message:
Sent: Tue June 10, 2025 07:22 AM
From: Tomas Kovacik
Subject: SVC pool extents rebalancing

Hi,

is it any different way how to re-balance extents within storage pool in SVC  ?   

for example when a  new controller is added

I'm  still using balance.pl from (Scripting tools for SAN Volume Controller released  in 2013)  

surprisingly still accessible here :

https://www.ibm.com/resources/mrs/assets/DownloadList?source=swg-SVCTools&lang=en_US

thanks

Tomas

------------------------------
Tomas Kovacik
------------------------------