GROUP COLLOCATION

[David_FA]

Hi!



We are tryng to implement COLLOCATION BY GROUP.



What would happend with the nodes that aren?t in a COLLOCATION group if we have stablished COLLOCATION BY GROUP in the Secuential Storage Pool?



Would TSM server consider those nodes as another collocation group?





Thanks in advance.

 

[chad_small]

I am wondering the same thing and plan on calling support to find out! I assume that only the nodes in the storage pool that are in the group would be collocated together but those in other storage pools that are in the collocation group would be collocated with those nodes in the same storage pool as they are.

 

[hogmaster]

The nodes not in a collocation group will go to separate media. Acting like Collocation by node.

This is quite usefull if you have some very large nodes. Mind you it will afeect your reclamamtion

if you have too many nodes not in a collocation group.



/regards Daniel Larsson

 

[Drewidian]

I am new to TSM and while we have not used collocation here, I definitely want to set it up. I just have a couple of questions regarding turning it on.

1) I only have 100 client nodes. If I turn on Collocation for 4 clients in a group and leave all of the other nodes out of the group, Will TSM setup all of the other clients as Collocation Nodes with a single tape being allocated to each client?

2) Once the nodes are in a collocation group, can I have the nodes in a different domain or use a different schedule?

Thanks in Advance.

The nodes not in a collocation group will go to separate media. Acting like Collocation by node.

This is quite usefull if you have some very large nodes. Mind you it will afeect your reclamamtion

if you have too many nodes not in a collocation group.



/regards Daniel Larsson

 

[iltoda]

h def stg states:

"If you specify COLLOCATE=GROUP but do not define any collocation
groups or if you specify COLLOCATE=GROUP but do not add nodes to a
collocation group, data is collocated by node. Be sure to consider
tape usage when organizing client nodes into collocation groups.
For example, if a tape-based storage pool consists of data from
grouped and ungrouped nodes and you specify COLLOCATE=GROUP, the
server does the following:
+ Collocates by group the data for grouped nodes only. Whenever
possible, the server collocates data belonging to a group of
nodes on a single tape or on as few tapes as possible. Data
for a single node can also be spread across several tapes
associated with a group.
+ Collocates by node the data for ungrouped nodes. Whenever
possible, the server stores the data for a single node on a
single tape. All available tapes that already have data for
the node are used before available space on any other tape is
used."

I have never tested it.

Marco

 

[ttrinh7975]

If I remember correctly, COLLOCATE=GROUP is available in v5.3+

 

[jideck]

process of collocation

1 change to collocation by group
2 make some new groups at list 2 (1 group=collocation by node)
--DEFINE COLLOCGROUP gr1
--DEFINE COLLOCGROUP gr2
3 assign nodes to groups
--DEFINE COLLOCMEMBER gr1 node1,node2,node3,node4
--DEFINE COLLOCMEMBER gr2 node5,node6,node7,node8
4 Check how bad it is for one of nodes (defragmenatation through media)
--select distinct node_name,volume_name,stgpool_name -
from volumeusage where node_name='node1'

all new backup will use new collocation order but old backup are unchenged to clean up make a new stg and use "move node data"

 

[jideck]

process of collocation

1 change to collocation by group
2 make some new groups at list 2 (1 group=collocation by node)
--DEFINE COLLOCGROUP gr1
--DEFINE COLLOCGROUP gr2
3 assign nodes to groups
--DEFINE COLLOCMEMBER gr1 node1,node2,node3,node4
--DEFINE COLLOCMEMBER gr2 node5,node6,node7,node8
4 Check how bad it is for one of nodes (defragmenatation through media)
--select distinct node_name,volume_name,stgpool_name -
from volumeusage where node_name='node1'

all new backup will use new collocation order but old backup are unchenged to clean up make a new stg and use "move node data"

---- also can be continued to apply to data already in backup
1. check how much data is in different collocation groups by checking node data
-- select rpad(NODE_NAME,30)node,sum(LOGICAL_MB)/1024/1024 as TB from occupancy -
group by node_name order by TB (move over some nodes to collocation group with less data dell collocmem and def collocmem)
2. move node data
-- MOVE NODEDATA fromstgpool=lto8-pool tostgpool=lto8-pool collocg=GR1 (or move between pools)