tablespace container design

[duoduo]

I want to know one thing, what is best design for tablespace
containers, of course, it is DB2 EE 7.2 on AIX 4.3.3.

For example, I have RAID 0+1 storage (8 disks) on EMC Symmetrix. Now I
need to create a 64GB tablespace on this EMC RAID. Which of the
following is the best way from performance perspective?

(1) 1 64GB container

(2) 4 * 16GB containers

(3) 8 * 8GB containers

[Philip Sherman]

Your RAID architecture (0+1) presents these disks to the system as a
single disk drive containing four physical drives using striping to
spread the data on them.

Which do you think is better - a single container on a drive or eight
small containers on a drive? I'd go with a single large container to
avoid seeks switching between containers. If read access is your primary
concern; then the +1 RAID should facilitate using two containers. In
this case; you would be able to read from both copies concurrently.
Other considerations would be a future need to expand the tablespace and
potential operating system buffering effects of having large files enabled.

The best answer I know of for your question is: it depends on the
workload and performance objectives.
Phil Sherman

duoduo wrote:

I want to know one thing, what is best design for tablespace
containers, of course, it is DB2 EE 7.2 on AIX 4.3.3.

For example, I have RAID 0+1 storage (8 disks) on EMC Symmetrix. Now I
need to create a 64GB tablespace on this EMC RAID. Which of the
following is the best way from performance perspective?

(1) 1 64GB container

(2) 4 * 16GB containers

(3) 8 * 8GB containers

[duoduo]

Thanks, Philip, I really appreciate your comments.
Philip Sherman <ps******@ameritech.net> wrote in message news:<Ff****************@newssvr15.news.prodigy.co m>...

Your RAID architecture (0+1) presents these disks to the system as a
single disk drive containing four physical drives using striping to
spread the data on them.

Which do you think is better - a single container on a drive or eight
small containers on a drive? I'd go with a single large container to
avoid seeks switching between containers. If read access is your primary
concern; then the +1 RAID should facilitate using two containers. In
this case; you would be able to read from both copies concurrently.
Other considerations would be a future need to expand the tablespace and
potential operating system buffering effects of having large files enabled.

The best answer I know of for your question is: it depends on the
workload and performance objectives.
Phil Sherman

duoduo wrote:

I want to know one thing, what is best design for tablespace
containers, of course, it is DB2 EE 7.2 on AIX 4.3.3.

For example, I have RAID 0+1 storage (8 disks) on EMC Symmetrix. Now I
need to create a 64GB tablespace on this EMC RAID. Which of the
following is the best way from performance perspective?

(1) 1 64GB container

(2) 4 * 16GB containers

(3) 8 * 8GB containers

[Dany]

Since you will be using Aix 4 I would only go with your option "(1) 1 64GB
container " if your are certain that it will never be bigger since 64GB file
on Aix 4 would be a "physical" limitation.

"duoduo" <du*********@gmail.com> wrote in message
news:d3**************************@posting.google.c om...

Thanks, Philip, I really appreciate your comments.
Philip Sherman <ps******@ameritech.net> wrote in message
news:<Ff****************@newssvr15.news.prodigy.co m>...

Your RAID architecture (0+1) presents these disks to the system as a
single disk drive containing four physical drives using striping to
spread the data on them.

Which do you think is better - a single container on a drive or eight
small containers on a drive? I'd go with a single large container to
avoid seeks switching between containers. If read access is your primary
concern; then the +1 RAID should facilitate using two containers. In
this case; you would be able to read from both copies concurrently.
Other considerations would be a future need to expand the tablespace and
potential operating system buffering effects of having large files
enabled.

The best answer I know of for your question is: it depends on the
workload and performance objectives.
Phil Sherman

duoduo wrote:

> I want to know one thing, what is best design for tablespace
> containers, of course, it is DB2 EE 7.2 on AIX 4.3.3.
>
> For example, I have RAID 0+1 storage (8 disks) on EMC Symmetrix. Now I
> need to create a 64GB tablespace on this EMC RAID. Which of the
> following is the best way from performance perspective?
>
> (1) 1 64GB container
>
> (2) 4 * 16GB containers
>
> (3) 8 * 8GB containers

[duoduo]

Dany, Thanks for your reply.

You are definitely right. JFS on AIX 4 has a 64GB file size
limitation, and I also have a 64GB 4k page size tablespace as well. I
am doing the test to migration the DB2 from 7.2 to 8.1 and AIX 4.3.3
to AIX 5L. Currently I am living on AIX 4.3.3

"Dany" <da******@videotron.ca> wrote in message news:<ci*********@news1.stadia.fi>...

Since you will be using Aix 4 I would only go with your option "(1) 1 64GB
container " if your are certain that it will never be bigger since 64GB file
on Aix 4 would be a "physical" limitation.

"duoduo" <du*********@gmail.com> wrote in message
news:d3**************************@posting.google.c om...

Thanks, Philip, I really appreciate your comments.
Philip Sherman <ps******@ameritech.net> wrote in message
news:<Ff****************@newssvr15.news.prodigy.co m>...

Your RAID architecture (0+1) presents these disks to the system as a
single disk drive containing four physical drives using striping to
spread the data on them.

Which do you think is better - a single container on a drive or eight
small containers on a drive? I'd go with a single large container to
avoid seeks switching between containers. If read access is your primary
concern; then the +1 RAID should facilitate using two containers. In
this case; you would be able to read from both copies concurrently.
Other considerations would be a future need to expand the tablespace and
potential operating system buffering effects of having large files
enabled.

The best answer I know of for your question is: it depends on the
workload and performance objectives.
Phil Sherman

duoduo wrote:
> I want to know one thing, what is best design for tablespace
> containers, of course, it is DB2 EE 7.2 on AIX 4.3.3.
>
> For example, I have RAID 0+1 storage (8 disks) on EMC Symmetrix. Now I
> need to create a 64GB tablespace on this EMC RAID. Which of the
> following is the best way from performance perspective?
>
> (1) 1 64GB container
>
> (2) 4 * 16GB containers
>
> (3) 8 * 8GB containers