Hi All,
Lot of time DBAs are asked to check the health of the Database,Health of the Database can be check in various ways.It includes:
SL No Monitoring Scope Current Status OS Level 1 Physical memory / Load :Load normal, Load averages: 0.35, 0.37, 0.36
2 OS Space threshold ( archive, ora_dump etc.. ) :Sufficient Space available.
3
Top 10 process consuming memory:No process using exceptional high memory
4 Free volumes available :Sufficient disk space is available on the mount points
5 Filesystem space Under normal threshold
Database level.
6 Check extents / Pro active Space addition:Space is being regularly added.
7 Check alert log for ORA- and warn messages.
8 Major wait events (latch/enqueue/Lib cache pin) No major wait events
9 Max Sessions
10 Long running Jobs 6 inactive sessions running for more than 8 hrs
11 Invalid objects 185
12 Analyze Jobs ( once in a week ) Done on 20-JAN-2008 Time 06:00:06
13 Temp usage / Rollback segment usage Normal
14 Nologging Indexes
15 Hotbackup/Coldbackup Gone fine
16 Redo generation normal
17 PQ proceses Normal
18 I/O Generation Under normal threshold
19 2 PC Pending transactions 0
DR / backup
1 Sync arch Normal
2 Purge arch Normal
3 Recovery status Normal
20)DATABASE HEALTH CHECK SCRIPT: Showing locks and Archive generation details
In Detail DATABASE Health check:OPERATING SYSTEM: 1)Physical memory/ Load:
1) Free:free command displays amount of total, free and used physical memory (RAM) in the system as well as showing information on shared memory, buffers, cached memory and swap space used by the Linux kernel.
Usage:
$ free -m
2) vmstat:vmstat reports report virtual memory statistics, which has information about processes, swap, free, buffer and cache memory, paging space, disk IO activity, traps, interrupts, context switches and CPU activity
Usage:
$vmstat 5
3) top:top command displays dynamic real-time view of the running tasks managed by kernel and in Linux system. The memory usage stats by top command include real-time live total, used and free physical memory and swap memory with their buffers and cached memory size respectively
Usage:
$top
4) ps :ps command reports a snapshot on information of the current active processes. ps will show the percentage of memory resource that is used by each process or task running in the system. With this command, top memory hogging processes can be identified.
Usage:
$ps aux
2) OS Space threshold ( archive, ora_dump etc.. ):
Checking the OS space is available in all filesystems,specially the location which is having archive logs ,oracle Database files.We can use the below OS commands:
$df –h
$du –csh *
3) Top 10 process consuming memory:
We can Displaying top 10 memory consuming processes as follows:
ps aux|head -1;ps aux|sort -m
We can use the top command, and press M which orders the process list by memory usage.
4) Free volumes available:
We have to make sure Sufficient disk space is available on the mount points on each OS servers where the Database is up and running.
$df –h
5)Filesystem space:
Under normal threshold.Check the filesystem in the OS side whether the sufficient space is available at all mount points.
DATABASE :6)Check extents / Pro active Space addition:
Check each of the Data,Index and temporary tablespaces for extend and blocks
Allocation details.
SET LINES 1000
SELECT SEGMENT_NAME,TABLESPACE_NAME,EXTENTS,BLOCKS
FROM DBA_SEGMENTS;
SELECT SEGMENT_NAME,TABLESPACE_NAME,EXTENTS,BLOCKS
FROM DBA_SEGMENTS WHERE TABLESPACE_NAME=’STAR01D’;
7) Check alert log for ORA- and warn messages:
Checking the alert log file regulary is a vital task we have to do.In the alert log files we have to looks for the following things:
1) Look for any of the oracle related errors.
Open the alert log file with less or more command and search for ORA-
This will give you the error details and time of occurrence.
2) Look for the Database level or Tablespace level changes
Monitor the alert log file and search the file for each Day activities happening
In the Database either whether it is bouncing of Database.Increase in the size of the tablespaces,Increase in the size of the Database parameters.In the 11g Database we can look for TNS errors in the alert log file.
8) Major wait events (latch/enqueue/Lib cache pin):
We can check the wait events details with the help of below queries:
SELECT s.saddr, s.SID, s.serial#, s.audsid, s.paddr, s.user#, s.username,
s.command, s.ownerid, s.taddr, s.lockwait, s.status, s.server,
s.schema#, s.schemaname, s.osuser, s.process, s.machine, s.terminal,
UPPER (s.program) program, s.TYPE, s.sql_address, s.sql_hash_value,
s.sql_id, s.sql_child_number, s.sql_exec_start, s.sql_exec_id,
s.prev_sql_addr, s.prev_hash_value, s.prev_sql_id,
s.prev_child_number, s.prev_exec_start, s.prev_exec_id,
s.plsql_entry_object_id, s.plsql_entry_subprogram_id,
s.plsql_object_id, s.plsql_subprogram_id, s.module, s.module_hash,
s.action, s.action_hash, s.client_info, s.fixed_table_sequence,
s.row_wait_obj#, s.row_wait_file#, s.row_wait_block#,
s.row_wait_row#, s.logon_time, s.last_call_et, s.pdml_enabled,
s.failover_type, s.failover_method, s.failed_over,
s.resource_consumer_group, s.pdml_status, s.pddl_status, s.pq_status,
s.current_queue_duration, s.client_identifier,
s.blocking_session_status, s.blocking_instance, s.blocking_session,
s.seq#, s.event#, s.event, s.p1text, s.p1, s.p1raw, s.p2text, s.p2,
s.p2raw, s.p3text, s.p3, s.p3raw, s.wait_class_id, s.wait_class#,
s.wait_class, s.wait_time, s.seconds_in_wait, s.state,
s.wait_time_micro, s.time_remaining_micro,
s.time_since_last_wait_micro, s.service_name, s.sql_trace,
s.sql_trace_waits, s.sql_trace_binds, s.sql_trace_plan_stats,
s.session_edition_id, s.creator_addr, s.creator_serial#
FROM v$session s
WHERE ( (s.username IS NOT NULL)
AND (NVL (s.osuser, 'x') <> 'SYSTEM')
AND (s.TYPE <> 'BACKGROUND') AND STATUS='ACTIVE'
)
ORDER BY "PROGRAM";
The following query provides clues about whether Oracle has been waiting for library cache activities:
Select sid, event, p1raw, seconds_in_wait, wait_time
From v$session_wait
Where event = 'library cache pin'
And state = 'WAITING';
The below Query gives details of Users sessions wait time and state:
SELECT NVL (s.username, '(oracle)') AS username, s.SID, s.serial#, sw.event,
sw.wait_time, sw.seconds_in_wait, sw.state
FROM v$session_wait sw, v$session s
WHERE s.SID = sw.SID
ORDER BY sw.seconds_in_wait DESC;
9) Max Sessions:
There should not be more than 6 inactive sessions running for more than 8 hours in a Database in order to minimize the consumption of CPU and I/O resources.
a)Users and Sessions CPU consumption can be obtained by below query:
Set lines 1000
select ss.username, se.SID,VALUE/100 cpu_usage_seconds
from v$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 and ss.status='ACTIVE'
and ss.username is not null
order by VALUE desc;
b) Users and Sessions CPU and I/O consumption can be obtained by below query:
-- shows Day wise,User wise,Process id of server wise- CPU and I/O consumption
set linesize 140
col spid for a6
col program for a35 trunc
select p.spid SPID,to_char(s.LOGON_TIME,'DDMonYY HH24:MI') date_login,s.username,decode(nvl(p.background,0),1,bg.description, s.program ) program,
ss.value/100 CPU,physical_reads disk_io,(trunc(sysdate,'J')-trunc(logon_time,'J')) days,
round((ss.value/100)/(decode((trunc(sysdate,'J')-trunc(logon_time,'J')),0,1,(trunc(sysdate,'J')-trunc(logon_time,'J')))),2) cpu_per_day
from V$PROCESS p,V$SESSION s,V$SESSTAT ss,V$SESS_IO si,V$BGPROCESS bg
where s.paddr=p.addr and ss.sid=s.sid
and ss.statistic#=12 and si.sid=s.sid
and bg.paddr(+)=p.addr
and round((ss.value/100),0) > 10
order by 8;
10) Long running Jobs:
We can find out long running jobs with the help of the below query:
col username for a20
col message for a50
col remaining for 9999
select username,to_char(start_time, 'hh24:mi:ss dd/mm/yy') started,
time_remaining remaining, message
from v$session_longops
where time_remaining = 0
order by time_remaining desc;
11) Invalid objects:
We can check the invalid objects with the help of the below query:
select owner||' '||object_name||' '||created||' '||status from dba_objects where status='INVALID';
12) Analyze Jobs ( once in a week ):
We need to analyze the jobs that are running once in a week as a golden rule.
The below steps can be considered for analyzing jobs.
Analyzing a Running Job
The status of a job or a task changes several times during its life cycle. A job can have the following as its status:
Scheduled: The job is created and will run at the specified time.
Running: The job is being executed and is in progress.
Initialization Error: The job or step could not be run successfully. If a step in a job fails initialization, the job status is Initialization Error.
Failed: The job was executed but failed.
Succeeded: The job was executed completely.
Stopped: The user canceled the job.
Stop Pending: The user has stopped the job. The already running steps are completing execution.
Suspended: This indicates that the execution of the job is deferred.
Inactive: This status indicates that the target has been deleted.
Reassigned: The owner of the job has changed.
Skipped: The job was not executed at the specified time and has been omitted.
The running jobs can be found out by the help of below query:
select sid, job,instance from dba_jobs_running;
We can find out the failed jobs and Broken jobs details with the help of the Below query:
select job||' '||schema_user||' '||Broken||' '||failures||' '||what||' '||last_date||' '||last_sec from dba_jobs;
13) Temp usage / Rollback segment/PGA usage:
We can get information of temporary tablespace usage details with the help of below query:
Set lines 1000
SELECT b.tablespace,
ROUND(((b.blocks*p.value)/1024/1024),2)||'M' "SIZE",
a.sid||','||a.serial# SID_SERIAL,
a.username,
a.program
FROM sys.v_$session a,
sys.v_$sort_usage b,
sys.v_$parameter p
WHERE p.name = 'db_block_size'
AND a.saddr = b.session_addr
ORDER BY b.tablespace, b.blocks;
We can get information of Undo tablespace usage details with the help of the below query:
set lines 1000
SELECT TO_CHAR(s.sid)||','||TO_CHAR(s.serial#) sid_serial,
NVL(s.username, 'None') orauser,
s.program,
r.name undoseg,
t.used_ublk * TO_NUMBER(x.value)/1024||'K' "Undo"
FROM sys.v_$rollname r,
sys.v_$session s,
sys.v_$transaction t,
sys.v_$parameter x
WHERE s.taddr = t.addr
AND r.usn = t.xidusn(+)
AND x.name = 'db_block_size';
We can get the PGA usage details with the help of the below query:
select st.sid "SID", sn.name "TYPE",
ceil(st.value / 1024 / 1024/1024) "GB"
from v$sesstat st, v$statname sn
where st.statistic# = sn.statistic#
and sid in
(select sid from v$session where username like UPPER('&user'))
and upper(sn.name) like '%PGA%'
order by st.sid, st.value desc;
Enter value for user: STARTXNAPP
14)Validating the Backup:
We have to verify the Hotbackup/Coldbackup(or any physical or logical backup) of all the Production and non-production Databases went fine.Make sure you are having a valid backups of all the Databases.Check the Backup locations to make sure the Backup completed on time with the required Backup data.
14)Hotbackup/Coldbackup:
Validating the backup of Database.It should complete on time with the required data for restoring and recovery purpose if required.
15) Redo generation/Archive logs generation details:
We should make sure there should not be frequent log switch happening in a Database.If there are frequent log switches than archive logs might generate more which may decrease the performance of the Database however in a production Database log switches could vary depending upon the Server configuration between 5 to 20.
We can the log switch details with the help of the below query:
Redolog switch Datewise and hourwise:
-------------------------------
set lines 120;
set pages 999;
select to_char(first_time,'DD-MON-RR') "Date",
to_char(sum(decode(to_char(first_time,'HH24'),'00',1,0)),'99') " 00",
to_char(sum(decode(to_char(first_time,'HH24'),'01',1,0)),'99') " 01",
to_char(sum(decode(to_char(first_time,'HH24'),'02',1,0)),'99') " 02",
to_char(sum(decode(to_char(first_time,'HH24'),'03',1,0)),'99') " 03",
to_char(sum(decode(to_char(first_time,'HH24'),'04',1,0)),'99') " 04",
to_char(sum(decode(to_char(first_time,'HH24'),'05',1,0)),'99') " 05",
to_char(sum(decode(to_char(first_time,'HH24'),'06',1,0)),'99') " 06",
to_char(sum(decode(to_char(first_time,'HH24'),'07',1,0)),'99') " 07",
to_char(sum(decode(to_char(first_time,'HH24'),'08',1,0)),'99') " 08",
to_char(sum(decode(to_char(first_time,'HH24'),'09',1,0)),'99') " 09",
to_char(sum(decode(to_char(first_time,'HH24'),'10',1,0)),'99') " 10",
to_char(sum(decode(to_char(first_time,'HH24'),'11',1,0)),'99') " 11",
to_char(sum(decode(to_char(first_time,'HH24'),'12',1,0)),'99') " 12",
to_char(sum(decode(to_char(first_time,'HH24'),'13',1,0)),'99') " 13",
to_char(sum(decode(to_char(first_time,'HH24'),'14',1,0)),'99') " 14",
to_char(sum(decode(to_char(first_time,'HH24'),'15',1,0)),'99') " 15",
to_char(sum(decode(to_char(first_time,'HH24'),'16',1,0)),'99') " 16",
to_char(sum(decode(to_char(first_time,'HH24'),'17',1,0)),'99') " 17",
to_char(sum(decode(to_char(first_time,'HH24'),'18',1,0)),'99') " 18",
to_char(sum(decode(to_char(first_time,'HH24'),'19',1,0)),'99') " 19",
to_char(sum(decode(to_char(first_time,'HH24'),'20',1,0)),'99') " 20",
to_char(sum(decode(to_char(first_time,'HH24'),'21',1,0)),'99') " 21",
to_char(sum(decode(to_char(first_time,'HH24'),'22',1,0)),'99') " 22",
to_char(sum(decode(to_char(first_time,'HH24'),'23',1,0)),'99') " 23"
from v$log_history
group by to_char(first_time,'DD-MON-RR')
order by 1
/
Archive logs generations is directly proportional to the number of log switches happening in a Database. If there are frequent log switches than archive logs might generate more which can affect the performance of Database.
We can use the below queries for archive logs generation details:
a)Archive logs by dates:
set lines 1000
select to_char(first_time,'DD-MON-RR') "Date",
to_char(sum(decode(to_char(first_time,'HH24'),'00',1,0)),'99') " 00",
to_char(sum(decode(to_char(first_time,'HH24'),'01',1,0)),'99') " 01",
to_char(sum(decode(to_char(first_time,'HH24'),'02',1,0)),'99') " 02",
to_char(sum(decode(to_char(first_time,'HH24'),'03',1,0)),'99') " 03",
to_char(sum(decode(to_char(first_time,'HH24'),'04',1,0)),'99') " 04",
to_char(sum(decode(to_char(first_time,'HH24'),'05',1,0)),'99') " 05",
to_char(sum(decode(to_char(first_time,'HH24'),'06',1,0)),'99') " 06",
to_char(sum(decode(to_char(first_time,'HH24'),'07',1,0)),'99') " 07",
to_char(sum(decode(to_char(first_time,'HH24'),'08',1,0)),'99') " 08",
to_char(sum(decode(to_char(first_time,'HH24'),'09',1,0)),'99') " 09",
to_char(sum(decode(to_char(first_time,'HH24'),'10',1,0)),'99') " 10",
to_char(sum(decode(to_char(first_time,'HH24'),'11',1,0)),'99') " 11",
to_char(sum(decode(to_char(first_time,'HH24'),'12',1,0)),'99') " 12",
to_char(sum(decode(to_char(first_time,'HH24'),'13',1,0)),'99') " 13",
to_char(sum(decode(to_char(first_time,'HH24'),'14',1,0)),'99') " 14",
to_char(sum(decode(to_char(first_time,'HH24'),'15',1,0)),'99') " 15",
to_char(sum(decode(to_char(first_time,'HH24'),'16',1,0)),'99') " 16",
to_char(sum(decode(to_char(first_time,'HH24'),'17',1,0)),'99') " 17",
to_char(sum(decode(to_char(first_time,'HH24'),'18',1,0)),'99') " 18",
to_char(sum(decode(to_char(first_time,'HH24'),'19',1,0)),'99') " 19",
to_char(sum(decode(to_char(first_time,'HH24'),'20',1,0)),'99') " 20",
to_char(sum(decode(to_char(first_time,'HH24'),'21',1,0)),'99') " 21",
to_char(sum(decode(to_char(first_time,'HH24'),'22',1,0)),'99') " 22",
to_char(sum(decode(to_char(first_time,'HH24'),'23',1,0)),'99') " 23"
from v$log_history
group by to_char(first_time,'DD-MON-RR')
order by 1
/
b)Archive log generation details Day-wise :
select to_char(COMPLETION_TIME,'DD-MON-YYYY'),count(*)
from v$archived_log group by to_char(COMPLETION_TIME,'DD-MON-YYYY')
order by to_char(COMPLETION_TIME,'DD-MON-YYYY');
c) Archive log count of the day:
select count(*)
from v$archived_log
where trunc(completion_time)=trunc(sysdate);
count of archived logs generated today on hourly basis:
-------------------------------------------------------
select to_char(first_time,'DD-MON-RR') "Date",
to_char(sum(decode(to_char(first_time,'HH24'),'00',1,0)),'99') " 00",
to_char(sum(decode(to_char(first_time,'HH24'),'01',1,0)),'99') " 01",
to_char(sum(decode(to_char(first_time,'HH24'),'02',1,0)),'99') " 02",
to_char(sum(decode(to_char(first_time,'HH24'),'03',1,0)),'99') " 03",
to_char(sum(decode(to_char(first_time,'HH24'),'04',1,0)),'99') " 04",
to_char(sum(decode(to_char(first_time,'HH24'),'05',1,0)),'99') " 05",
to_char(sum(decode(to_char(first_time,'HH24'),'06',1,0)),'99') " 06",
to_char(sum(decode(to_char(first_time,'HH24'),'07',1,0)),'99') " 07",
to_char(sum(decode(to_char(first_time,'HH24'),'08',1,0)),'99') " 08",
to_char(sum(decode(to_char(first_time,'HH24'),'09',1,0)),'99') " 09",
to_char(sum(decode(to_char(first_time,'HH24'),'10',1,0)),'99') " 10",
to_char(sum(decode(to_char(first_time,'HH24'),'11',1,0)),'99') " 11",
to_char(sum(decode(to_char(first_time,'HH24'),'12',1,0)),'99') " 12",
to_char(sum(decode(to_char(first_time,'HH24'),'13',1,0)),'99') " 13",
to_char(sum(decode(to_char(first_time,'HH24'),'14',1,0)),'99') " 14",
to_char(sum(decode(to_char(first_time,'HH24'),'15',1,0)),'99') " 15",
to_char(sum(decode(to_char(first_time,'HH24'),'16',1,0)),'99') " 16",
to_char(sum(decode(to_char(first_time,'HH24'),'17',1,0)),'99') " 17",
to_char(sum(decode(to_char(first_time,'HH24'),'18',1,0)),'99') " 18",
to_char(sum(decode(to_char(first_time,'HH24'),'19',1,0)),'99') " 19",
to_char(sum(decode(to_char(first_time,'HH24'),'20',1,0)),'99') " 20",
to_char(sum(decode(to_char(first_time,'HH24'),'21',1,0)),'99') " 21",
to_char(sum(decode(to_char(first_time,'HH24'),'22',1,0)),'99') " 22",
to_char(sum(decode(to_char(first_time,'HH24'),'23',1,0)),'99') " 23"
from v$log_history
where to_char(first_time,'DD-MON-RR')='16-AUG-10'
group by to_char(first_time,'DD-MON-RR')
order by 1
/
16)I/O Generation:
We can find out CPU and I/O generation details for all the users in the Database with the help of the below query:
-- Show IO per session,CPU in seconds, sessionIOS.
set linesize 140
col spid for a6
col program for a35 trunc
select p.spid SPID,to_char(s.LOGON_TIME,'DDMonYY HH24:MI') date_login,s.username,decode(nvl(p.background,0),1,bg.description, s.program ) program,
ss.value/100 CPU,physical_reads disk_io,(trunc(sysdate,'J')-trunc(logon_time,'J')) days,
round((ss.value/100)/(decode((trunc(sysdate,'J')-trunc(logon_time,'J')),0,1,(trunc(sysdate,'J')-trunc(logon_time,'J')))),2) cpu_per_day
from V$PROCESS p,V$SESSION s,V$SESSTAT ss,V$SESS_IO si,V$BGPROCESS bg
where s.paddr=p.addr and ss.sid=s.sid
and ss.statistic#=12 and si.sid=s.sid
and bg.paddr(+)=p.addr
and round((ss.value/100),0) > 10
order by 8;
To know what the session is doing and what kind of sql it is using:
-- what kind of sql a session is using
set lines 9999
set pages 9999
select s.sid, q.sql_text from v$sqltext q, v$session s
where q.address = s.sql_address
and s.sid = &sid order by piece;
eg: sid=1853
17)Sync arch:
In a Dataguard environment we have to check primary is in sync with the secondary Database.This we can check as follows:
The V$ MANAGED_STANDBY view on the standby database site shows you the activities performed by
both redo transport and Redo Apply processes in a Data Guard environment
SELECT PROCESS, CLIENT_PROCESS, SEQUENCE#, STATUS FROM V$MANAGED_STANDBY;
In some situations, automatic gap recovery may not take place and you will need to perform gap recovery manually. For example, you will need to perform gap recovery manually if you are using logical standby databases and the primary database is not available.
The following sections describe how to query the appropriate views to determine which log files are missing and perform manual recovery.
On a physical standby database
To determine if there is an archive gap on your physical standby database, query the V$ARCHIVE_GAP view as shown in the following example:
SQL> SELECT * FROM V$ARCHIVE_GAP;
If it displays no rows than the primary Database is in sync with the standy Database.If it display any information with row than manually we have to apply the archive logs.
After you identify the gap, issue the following SQL statement on the primary database to locate the archived redo log files on your primary database (assuming the local archive destination on the primary database is LOG_ARCHIVE_DEST_1):
Eg:
SELECT NAME FROM V$ARCHIVED_LOG WHERE THREAD#=1 AND DEST_ID=1 AND SEQUENCE# BETWEEN 7 AND 10;
Copy these log files to your physical standby database and register them using the ALTER DATABASE REGISTER LOGFILE statement on your physical standby database. For example:
SQL> ALTER DATABASE REGISTER LOGFILE
'/physical_standby1/thread1_dest/arcr_1_7.arc';
SQL> ALTER DATABASE REGISTER LOGFILE
'/physical_standby1/thread1_dest/arcr_1_8.arc';
After you register these log files on the physical standby database, you can restart Redo Apply. The V$ARCHIVE_GAP fixed view on a physical standby database only returns the next gap that is currently blocking Redo Apply from continuing. After resolving the gap and starting Redo Apply, query the V$ARCHIVE_GAP fixed view again on the physical standby database to determine the next gap sequence, if there is one. Repeat this process until there are no more gaps.
On a logical standby database:
To determine if there is an archive gap, query the DBA_LOGSTDBY_LOG view on the logical standby database. For example, the following query indicates there is a gap in the sequence of archived redo log files because it displays two files for THREAD 1 on the logical standby database. (If there are no gaps, the query will show only one file for each thread.) The output shows that the highest registered file is sequence number 10, but there is a gap at the file shown as sequence number 6:
SQL> COLUMN FILE_NAME FORMAT a55
SQL> SELECT THREAD#, SEQUENCE#, FILE_NAME FROM DBA_LOGSTDBY_LOG L
2> WHERE NEXT_CHANGE# NOT IN
3> (SELECT FIRST_CHANGE# FROM DBA_LOGSTDBY_LOG WHERE L.THREAD# = THREAD#)
4> ORDER BY THREAD#,SEQUENCE#;
THREAD# SEQUENCE# FILE_NAME
---------- ---------- -----------------------------------------------
1 6 /disk1/oracle/dbs/log-1292880008_6.arc
1 10 /disk1/oracle/dbs/log-1292880008_10.arc
Copy the missing log files, with sequence numbers 7, 8, and 9, to the logical standby system and register them using the ALTER DATABASE REGISTER LOGICAL LOGFILE statement on your logical standby database. For example:
SQL> ALTER DATABASE REGISTER LOGICAL LOGFILE '/disk1/oracle/dbs/log-1292880008_10.arc';
After you register these log files on the logical standby database, you can restart SQL Apply.
The DBA_LOGSTDBY_LOG view on a logical standby database only returns the next gap that is currently blocking SQL Apply from continuing. After resolving the identified gap and starting SQL Apply, query the DBA_LOGSTDBY_LOG view again on the logical standby database to determine the next gap sequence, if there is one. Repeat this process until there are no more gaps.
Monitoring Log File Archival Information:
Step 1 Determine the current archived redo log file sequence numbers.
Enter the following query on the primary database to determine the current archived redo log file sequence numbers:
SQL> SELECT THREAD#, SEQUENCE#, ARCHIVED, STATUS FROM V$LOG
WHERE STATUS='CURRENT';
Step 2 Determine the most recent archived redo log file.
Enter the following query at the primary database to determine which archived redo log file contains the most recently transmitted redo data:
SQL> SELECT MAX(SEQUENCE#), THREAD# FROM V$ARCHIVED_LOG GROUP BY THREAD#;
Step 3 Determine the most recent archived redo log file at each destination.
Enter the following query at the primary database to determine which archived redo log file was most recently transmitted to each of the archiving destinations:
SQL> SELECT DESTINATION, STATUS, ARCHIVED_THREAD#, ARCHIVED_SEQ#
2> FROM V$ARCHIVE_DEST_STATUS
3> WHERE STATUS <> 'DEFERRED' AND STATUS <> 'INACTIVE';
DESTINATION STATUS ARCHIVED_THREAD# ARCHIVED_SEQ#
------------------ ------ ---------------- -------------
/private1/prmy/lad VALID 1 947
standby1 VALID 1 947
The most recently written archived redo log file should be the same for each archive destination listed. If it is not, a status other than VALID might identify an error encountered during the archival operation to that destination.
Step 4 Find out if archived redo log files have been received.
You can issue a query at the primary database to find out if an archived redo log file was not received at a particular site. Each destination has an ID number associated with it. You can query the DEST_ID column of the V$ARCHIVE_DEST fixed view on the primary database to identify each destination's ID number.
Assume the current local destination is 1, and one of the remote standby destination IDs is 2. To identify which log files are missing at the standby destination, issue the following query:
SQL> SELECT LOCAL.THREAD#, LOCAL.SEQUENCE# FROM
2> (SELECT THREAD#, SEQUENCE# FROM V$ARCHIVED_LOG WHERE DEST_ID=1)
3> LOCAL WHERE
4> LOCAL.SEQUENCE# NOT IN
5> (SELECT SEQUENCE# FROM V$ARCHIVED_LOG WHERE DEST_ID=2 AND
6> THREAD# = LOCAL.THREAD#);
THREAD# SEQUENCE#
--------- ---------
1 12
1 13
1 14
18)Purge arch:
We have to make sure the archive logs files are purged safely or move to Tape drive or any other location in order to make space for new archive logs files in the Archive logs destination locations.
19)Recovery status:
In order to do recover make sure you are having latest archive logs,so that you can restore and do the recovery if required.
20) MY DATABASE HEALTH CHECK SCRIPT:/* SCRIPT FOR MONITORING AND CHECKING HEALTH OF DATABASE-USEFUL FOR PRODUCTION DATABASES */
-- SHOWS RUNNING JOBS
select 'RUNNING JOBS', sid, job,instance from dba_jobs_running;
set lines 1000
-- SHOWS ARCHIVE LOGS GENERAION DETAILS HOURLY AND DATE WISE BASIS
select 'ARCHIVE LOG REPORT',to_char(first_time,'DD-MON-RR') "Date",
to_char(sum(decode(to_char(first_time,'HH24'),'00',1,0)),'99') " 00",
to_char(sum(decode(to_char(first_time,'HH24'),'01',1,0)),'99') " 01",
to_char(sum(decode(to_char(first_time,'HH24'),'02',1,0)),'99') " 02",
to_char(sum(decode(to_char(first_time,'HH24'),'03',1,0)),'99') " 03",
to_char(sum(decode(to_char(first_time,'HH24'),'04',1,0)),'99') " 04",
to_char(sum(decode(to_char(first_time,'HH24'),'05',1,0)),'99') " 05",
to_char(sum(decode(to_char(first_time,'HH24'),'06',1,0)),'99') " 06",
to_char(sum(decode(to_char(first_time,'HH24'),'07',1,0)),'99') " 07",
to_char(sum(decode(to_char(first_time,'HH24'),'08',1,0)),'99') " 08",
to_char(sum(decode(to_char(first_time,'HH24'),'09',1,0)),'99') " 09",
to_char(sum(decode(to_char(first_time,'HH24'),'10',1,0)),'99') " 10",
to_char(sum(decode(to_char(first_time,'HH24'),'11',1,0)),'99') " 11",
to_char(sum(decode(to_char(first_time,'HH24'),'12',1,0)),'99') " 12",
to_char(sum(decode(to_char(first_time,'HH24'),'13',1,0)),'99') " 13",
to_char(sum(decode(to_char(first_time,'HH24'),'14',1,0)),'99') " 14",
to_char(sum(decode(to_char(first_time,'HH24'),'15',1,0)),'99') " 15",
to_char(sum(decode(to_char(first_time,'HH24'),'16',1,0)),'99') " 16",
to_char(sum(decode(to_char(first_time,'HH24'),'17',1,0)),'99') " 17",
to_char(sum(decode(to_char(first_time,'HH24'),'18',1,0)),'99') " 18",
to_char(sum(decode(to_char(first_time,'HH24'),'19',1,0)),'99') " 19",
to_char(sum(decode(to_char(first_time,'HH24'),'20',1,0)),'99') " 20",
to_char(sum(decode(to_char(first_time,'HH24'),'21',1,0)),'99') " 21",
to_char(sum(decode(to_char(first_time,'HH24'),'22',1,0)),'99') " 22",
to_char(sum(decode(to_char(first_time,'HH24'),'23',1,0)),'99') " 23"
from v$log_history
group by to_char(first_time,'DD-MON-RR')
order by 1
/
-- WHAT ALL THE SESSIONS ARE GETTING BLOCKED
select 'SESSIONS BLOCKED',process,sid, blocking_session from v$session where blocking_session is not null;
-- WHICH SESSION IS BLOCKING WHICH SESSION
set lines 9999
set pages 9999
select s1.username || '@' || s1.machine
|| ' ( SID=' || s1.sid || ' ) is blocking '
|| s2.username || '@' || s2.machine || ' ( SID=' || s2.sid || ' ) ' AS blocking_status
from v$lock l1, v$session s1, v$lock l2, v$session s2
where s1.sid=l1.sid and s2.sid=l2.sid
and l1.BLOCK=1 and l2.request > 0
and l1.id1 = l2.id1
and l2.id2 = l2.id2 ;
-- SHOWS BLOCK CHANGES DETAILS AND PHYSICAL READS DETAIL
select a.sid,b.username,block_gets,consistent_gets,physical_reads,block_changes
from V$SESS_IO a,V$SESSION b
where a.sid=b.sid and block_changes > 10000 order by block_changes desc;
-- show IO per session / CPU in seconds. sessionIOS.sql
set linesize 140
col spid for a6
col program for a35 trunc
select p.spid SPID,to_char(s.LOGON_TIME,'DDMonYY HH24:MI') date_login,s.username,decode(nvl(p.background,0),1,bg.description, s.program ) program,ss.value/100 CPU,physical_reads disk_io,(trunc(sysdate,'J')-trunc(logon_time,'J')) days,round((ss.value/100)/(decode((trunc(sysdate,'J')-trunc(logon_time,'J')),0,1,(trunc(sysdate,'J')-trunc(logon_time,'J')))),2) cpu_per_day
from V$PROCESS p,V$SESSION s,V$SESSTAT ss,V$SESS_IO si,V$BGPROCESS bg
where s.paddr=p.addr and ss.sid=s.sid
and ss.statistic#=12 and si.sid=s.sid
and bg.paddr(+)=p.addr
and round((ss.value/100),0) > 10
order by 8;
-- SCRIPT TO IDENTIFY LONG RUNNING STATEMENTS
rem LONGOPS.SQL
rem Long Running Statements
rem Helmut Pfau, Oracle Deutschland GmbH
set linesize 120
col opname format a20
col target format a15
col units format a10
col time_remaining format 99990 heading Remaining[s]
col bps format 9990.99 heading [Units/s]
col fertig format 90.99 heading "complete[%]"
select sid,
opname,
target,
sofar,
totalwork,
units,
(totalwork-sofar)/time_remaining bps,
time_remaining,
sofar/totalwork*100 fertig
from v$session_longops
where time_remaining > 0
/
-- ACTIVE SESSIONS IN DATABASE
select 'ACTIVE SESSION', sid, serial#,machine, osuser,username,status from v$session where username!='NULL' and status='ACTIVE';
-- WHAT SQL A SESSION IS USING
set lines 9999
set pages 9999
select s.sid, q.sql_text from v$sqltext q, v$session s
where q.address = s.sql_address
and s.sid = &sid order by piece;
eg:SID=1844
I would like to add one more script which will tell me details regarding the Size of the Database used,occupied and available and Tablespace usage
details along with hit ratio of various SGA components which can be very helpfull
to monitor the performance of the Databases.
Database_monitor.sql:ttitle "1. :============== Tablespace Usage Information ==================:" skip 2
set linesize 140
col Total format 99999.99 heading "Total space(MB)"
col Used format 99999.99 heading "Used space(MB)"
col Free format 99999.99 heading "Free space(MB)"
break on report
compute sum of Total space(MB) on report
compute sum of Used space(MB) on report
compute sum of Free space(MB) on report
select a.tablespace_name, round(a.bytes/1024/1024,2) Total,
round( nvl( b.bytes,0)/1024/1024,2) Used,
round(nvl(c.bytes, 0)/1024/1024,2) Free ,
round(nvl(b.bytes,0)*100/nvl(a.bytes,0),2) "% Used"
from sys.sm$ts_avail a, sys.sm$ts_used b, sys.sm$ts_free c
where a.tablespace_name=b.tablespace_name(+)
and b.tablespace_name=c.tablespace_name(+);
ttitle "2. :============== Hit Ratio Information ==================:" skip 2
set linesize 80
clear columns
clear breaks
set pagesize 60 heading off termout off echo off verify off
REM
col val1 new_val lib noprint
select 100*(1-(SUM(Reloads)/SUM(Pins))) val1
from V$LIBRARYCACHE;
ttitle off
col val2 new_val dict noprint
select 100*(1-(SUM(Getmisses)/SUM(Gets))) val2
from V$ROWCACHE;
ttitle off
col val3 new_val phys_reads noprint
select Value val3
from V$SYSSTAT
where Name = 'physical reads';
ttitle off
col val4 new_val log1_reads noprint
select Value val4
from V$SYSSTAT
where Name = 'db block gets';
ttitle off
col val5 new_val log2_reads noprint
select Value val5
from V$SYSSTAT
where Name = 'consistent gets';
ttitle off
col val6 new_val chr noprint
select 100*(1-(&phys_reads / (&log1_reads + &log2_reads))) val6
from DUAL;
ttitle off
col val7 new_val avg_users_cursor noprint
col val8 new_val avg_stmts_exe noprint
select SUM(Users_Opening)/COUNT(*) val7,
SUM(Executions)/COUNT(*) val8
from V$SQLAREA;
ttitle off
set termout on
set heading off
ttitle -
center 'SGA Cache Hit Ratios' skip 2
select 'Data Block Buffer Hit Ratio : '||&chr db_hit_ratio,
' Shared SQL Pool ',
' Dictionary Hit Ratio : '||&dict dict_hit,
' Shared SQL Buffers (Library Cache) ',
' Cache Hit Ratio : '||&lib lib_hit,
' Avg. Users/Stmt : '||
&avg_users_cursor||' ',
' Avg. Executes/Stmt : '||
&avg_stmts_exe||' '
from DUAL;
ttitle "3. :============== Sort Information ==================:" skip 2
select A.Value Disk_Sorts,
B.Value Memory_Sorts,
ROUND(100*A.Value/
DECODE((A.Value+B.Value),0,1,(A.Value+B.Value)),2)
Pct_Disk_Sorts
from V$SYSSTAT A, V$SYSSTAT B
where A.Name = 'sorts (disk)'
and B.Name = 'sorts (memory)';
ttitle "4. :============== Database Size Information ==================:" skip 2
select sum(bytes/1024/1024/1024) Avail from sm$ts_avail union all select sum(bytes/1024/1024/1024) Used from sm$ts_used union all select sum(bytes/1024/1024/1024) Free from sm$ts_free;
Hope this helps you in monitoring your Databases.
Best regards,
Rafi.
