DBA Scripts - Very Useful - 4. Session Statistics

Here are some scripts related to Session Statistics .

Session I/O By User

SESSION I/O BY USER NOTES:

  Username - Name of the Oracle process user

  OS User - Name of the operating system user

  PID - Process ID of the session

  SID - Session ID of the session

  Serial# - Serial# of the session

  Physical Reads - Physical reads for the session

  Block Gets - Block gets for the session

  Consistent Gets - Consistent gets for the session

  Block Changes - Block changes for the session

  Consistent Changes - Consistent changes for the session

select       nvl(ses.USERNAME,'ORACLE PROC') username,

               OSUSER os_user,

               PROCESS pid,

               ses.SID sid,

               SERIAL#,

               PHYSICAL_READS,

               BLOCK_GETS,

               CONSISTENT_GETS,

               BLOCK_CHANGES,

               CONSISTENT_CHANGES

from        v$session ses, 

               v$sess_io sio

where       ses.SID = sio.SID

order        by PHYSICAL_READS, ses.USERNAME

CPU Usage By Session

CPU USAGE BY SESSION NOTES:

  Username - Name of the user

  SID - Session id

  CPU Usage - CPU centiseconds used by this session (divide by 100 to get real CPU seconds)

select       nvl(ss.USERNAME,'ORACLE PROC') username,

               se.SID,

               VALUE cpu_usage

from        v$session ss, 

               v$sesstat se, 

               v$statname sn

where       se.STATISTIC# = sn.STATISTIC#

and          NAME like '%CPU used by this session%'

and          se.SID = ss.SID

order        by VALUE desc

Resource Usage By User

RESOURCE USAGE BY USER NOTES:

  SID - Session ID

  Username - Name of the user

  Statistic - Name of the statistic

  Value - Current value

select       ses.SID,

               nvl(ses.USERNAME,'ORACLE PROC') username,

               sn.NAME statistic,

               sest.VALUE

from        v$session ses, 

               v$statname sn, 

               v$sesstat sest

where       ses.SID = sest.SID

and          sn.STATISTIC# = sest.STATISTIC#

and          sest.VALUE is not null

and          sest.VALUE != 0            

order        by ses.USERNAME, ses.SID, sn.NAME

Session Stats By Session

SESSION STAT NOTES:

  Username - Name of the user

  SID - Session ID

  Statistic - Name of the statistic

  Usage - Usage according to Oracle

select  nvl(ss.USERNAME,'ORACLE PROC') username,

               se.SID,

               sn.NAME stastic,

               VALUE usage

from        v$session ss, 

               v$sesstat se, 

               v$statname sn

where       se.STATISTIC# = sn.STATISTIC#

and          se.SID = ss.SID

and          se.VALUE > 0

order        by sn.NAME, se.SID, se.VALUE desc

Cursor Usage By Session

CURSOR USAGE BY SESSION NOTES:

  Username - Name of the user

  Recursive Calls - Total number of recursive calls

  Opened Cursors - Total number of opened cursors

  Current Cursors - Number of cursor currently in use

select       user_process username,

               "Recursive Calls",

               "Opened Cursors",

               "Current Cursors"

from  (

               select       nvl(ss.USERNAME,'ORACLE PROC')||'('||se.sid||') ' user_process, 

                                              sum(decode(NAME,'recursive calls',value)) "Recursive Calls",

                                              sum(decode(NAME,'opened cursors cumulative',value)) "Opened Cursors",

                                              sum(decode(NAME,'opened cursors current',value)) "Current Cursors"

               from        v$session ss, 

                               v$sesstat se, 

                               v$statname sn

               where       se.STATISTIC# = sn.STATISTIC#

               and          (NAME  like '%opened cursors current%'

               or             NAME  like '%recursive calls%'

               or             NAME  like '%opened cursors cumulative%')

               and          se.SID = ss.SID

               and          ss.USERNAME is not null

               group       by nvl(ss.USERNAME,'ORACLE PROC')||'('||se.SID||') '

)

orasnap_user_cursors

order        by USER_PROCESS,"Recursive Calls"

User Hit Ratios

USER HIT RATIO NOTES:

  Username - Name of the user

  Consistent Gets - The number of accesses made to the block buffer to retrieve data in a consistent mode.

  DB Blk Gets - The number of blocks accessed via single block gets (i.e. not through the consistent get mechanism).

  Physical Reads - The cumulative number of blocks read from disk.

  Logical reads are the sum of consistent gets and db block gets.

  The db block gets statistic value is incremented when a block is read for update and when segment header blocks are accessed.

  Hit ratio should be > 90%

select       USERNAME,

               CONSISTENT_GETS,

        BLOCK_GETS,

        PHYSICAL_READS,

        ((CONSISTENT_GETS+BLOCK_GETS-PHYSICAL_READS) / (CONSISTENT_GETS+BLOCK_GETS)) Ratio

from        v$session, v$sess_io

where       v$session.SID = v$sess_io.SID

and          (CONSISTENT_GETS+BLOCK_GETS) > 0

and          USERNAME is not null

order        by ((CONSISTENT_GETS+BLOCK_GETS-PHYSICAL_READS) / (CONSISTENT_GETS+BLOCK_GETS))