>> How can we see the size of this file(filled size).
You can NOT ask the OS about the filled size. It does not know that's why they call it a 'raw' device.
The OS will know the allocated size: vgdisplay, lvdisplay...
The application (oracle) knows the used size. Ask it kindly.
You could possibly use 'dd' to make a copy/backup either copying everything, or copying as much as t oracle thinks it is using.
Using dd is tedious and error prone, thus discouraged.
You would drive it with information obtained through SQL with queries similar to:
column status format a8
column member format a55
column file_name format a45
column Tablespace format a15
column segment_name format a15
column extent_name format a15
column owner format a10
column file format a45
column id format 99
set pages 9999
set heading off
set FEEDBACK off
select 'redo_'||l.group# "Tablespace", l.group# "Id", l.bytes/(1024*1024) "MB",
MEMBER "File" from v$logfile f, v$log l where l.group# = f.group#
union
select tablespace_name "Tablespace", FILE_ID "Id", bytes/(1024*1024) "MB",
file_name "File" from dba_data_files
union
select tablespace_name "Tablespace", FILE_ID "Id", bytes/(1024*1024) "MB",
file_name "File" from dba_temp_files
union
select 'Control_file' "Tablespace", rownum "Id", 0 "MB",
name "File" from v$controlfile
order by 1
/
The last part of that union applies to the specific raw device you ask about.
Hope this helps some,
Hein van den Heuvel (at gmail dot com)
HvdH Performance Consulting
