extent management local

[ashley75]

could someone explain to me what is

'EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1024K'


how should we size the extents ??? and what value to be efficient ??? what happen if your extent is too big ???

Thanks

[marist89]

This topic has been discussed several times on this forum. Use http://www.dbasupport.com/forums/search.php and search for LMT

[mrvajrala]

You may have a LOCALLY MANAGED TABLESPACE.

that means , Oracle manages the space requirements for that tablespace locally and eleiminates the burden on data dictionary , and its a good deal for performance, coz oracle doesnt need to write/update the dictionary.

'EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1024K'

In the above syntax .. extents will be allocated to the objects in 1MB each time a request is generated.

Thanks,
Madhu

[dba1]

If your extent is too big, your tablespace get extended less frequently. But your disk may not be used efficiently because you have more unused space in your tablespace.

[ashley75]

how do you check to see for the unused space on your tablespace ???

Thanks

[mrvajrala]

Since this is a LOCALLY Managed tablespace , you can not check the DBA_FREE_SPACE for the un used space.

Well here we have some views :

select bytes_used,bytes_cached from v$temp_extent_pool;

another views to look at are
v$temp_space_header
v$temp_extent_map

V$sort_usage
v$sort_segment

You have to fight with the above view ...

Madhu

[pando]

Originally posted by mrvajrala
Since this is a LOCALLY Managed tablespace , you can not check the DBA_FREE_SPACE for the un used space.

joking? or you really mean locally managed TEMPORARY Tablespace with TEMPFILE?

[jmodic]

Originally posted by mrvajrala
Since this is a LOCALLY Managed tablespace , you can not check the DBA_FREE_SPACE for the un used space.
....SNIP.....

That's not true, I think you've confused that with localy managed temporary tablespace! For other permanent localy managed tablespaces DBA_FREE_SPACE still works the same way as in the old days.

[mrvajrala]

Yep , I really Joked ...

Its Locally Managed Temporary tablespace....