Maximum number of STRIPE SETS in a Tablespace

[Mark A]

I have an OLTP database that has a tablespace that will start out at about 1
TB, but may grow to 75 TB's in size over the next 5 years. When I add new
containers (on a new mount point), I want to use the BEGIN NEW STRIPE SET
command to avoid rebalancing.

Anyone know the maximum number of STRIPE SET's that can be created for a
tablespace.

[Mark A]

"Mark A" <no****@nowhere.comwrote in message
news:YR*****************@bignews8.bellsouth.net...

>I have an OLTP database that has a tablespace that will start out at about
1 TB, but may grow to 75 TB's in size over the next 5 years. When I add new
containers (on a new mount point), I want to use the BEGIN NEW STRIPE SET
command to avoid rebalancing.

Anyone know the maximum number of STRIPE SET's that can be created for a
tablespace.

Correction:

The maximum size of a large tablespace is 16 TB's, so even though my
database will grow to 75 TB's, I will be using multiple tablespaces to stay
under the 16 TB limit. But I still need to add a lot of STRIPE SETs over
time, and need to know the maximum number per tablespace.

[Ajean]

On 8ÔÂ6ÈÕ, ÏÂÎç10ʱ56·Ö, "Mark A" <[e-mail]:

"Mark A" <[e-mail] in message

news:YR*****************@bignews8.bellsouth.net...

I have an OLTP database that has a tablespace that will start out at about
1 TB, but may grow to 75 TB's in size over the next 5 years. When I add new
containers (on a new mount point), I want to use the BEGIN NEW STRIPE SET
command to avoid rebalancing.

Anyone know the maximum number of STRIPE SET's that can be created for a
tablespace.

Correction:

The maximum size of a large tablespace is 16 TB's, so even though my
database will grow to 75 TB's, I will be using multiple tablespaces to stay
under the 16 TB limit. But I still need to add a lot of STRIPE SETs over
time, and need to know the maximum number per tablespace.

OH,db2 has this limited?
How can we break it?
add another tablespace?

[Mark A]

>"Ajean" <je*********@gmail.comwrote in message

>news:eb2c1b24-16d7-4f4c-b4cd->9f**********@z6g2000pre.googlegroups.com...
OH,db2 has this limited?
How can we break it?
add another tablespace?

I need to know how many time I can extend a tablespace by adding new
containers in a new stripe set to avoid rebalancing. I don't care about the
maximum tablespace size of 16TB, it is not relevant to my question.

[kschlamb]

On Aug 8, 10:47 pm, "Mark A" <[e-mail]:

"Ajean" <[e-mail] in message
news:eb2c1b24-16d7-4f4c-b4cd->9f8507af7__BEGIN_MASK_n#9g02mG7!__...__********** ************@z6g2000pre.googlegroups.com...
OH,db2 has this limited?
How can we break it?
add another tablespace?

I need to know how many time I can extend a tablespace by adding new
containers in a new stripe set to avoid rebalancing. I don't care about the
maximum tablespace size of 16TB, it is not relevant to my question.

Hi Mark,

There is in fact a limit but it is not a specific number of stripe
sets. The limit is on the size of the tablespace's map (which is
limited to about 44K in V9.1 and later). This map is made up of one
or more ranges (you can see this as part of a tablespace snapshot) and
generally you have one range per stripe set (if all of the containers
within a stripe set are the same size then there is only range; you
get more ranges if the containers have different sizes -- which is not
recommended).

The size of each individual range in a tablespace (and this is where
the 'it depends' part comes in) is based on the maximum number of
containers in any of the stripe sets in the tablespace (as an aside,
if you're creating multiple stripe sets then ideally you will have the
same number of containers in each stripe set, so as to give you
consistent striping across the tablespace).

I won't get into the specifics of the formula here but let's consider
an example where you have 4 containers per stripe set. In that case,
you'll be able to fit about 750 ranges (stripe sets, assuming one
range per stripe set) in the tablespace. If you have a specific
configuration in mind then let me know.

Hope that helps.

Kelly Schlamb

[Mark A]

<ks******@ca.ibm.comwrote in message
news:41**********************************@25g2000h sx.googlegroups.com...

Hi Mark,

There is in fact a limit but it is not a specific number of stripe
sets. The limit is on the size of the tablespace's map (which is
limited to about 44K in V9.1 and later). This map is made up of one
or more ranges (you can see this as part of a tablespace snapshot) and
generally you have one range per stripe set (if all of the containers
within a stripe set are the same size then there is only range; you
get more ranges if the containers have different sizes -- which is not
recommended).

The size of each individual range in a tablespace (and this is where
the 'it depends' part comes in) is based on the maximum number of
containers in any of the stripe sets in the tablespace (as an aside,
if you're creating multiple stripe sets then ideally you will have the
same number of containers in each stripe set, so as to give you
consistent striping across the tablespace).

I won't get into the specifics of the formula here but let's consider
an example where you have 4 containers per stripe set. In that case,
you'll be able to fit about 750 ranges (stripe sets, assuming one
range per stripe set) in the tablespace. If you have a specific
configuration in mind then let me know.

Hope that helps.

Kelly Schlamb

Thanks.