Online Backups taking long time.

[Former Member]

Hello,

Recently we have restarted all our sap servers which are running on HP-UX.

Before doing this activity the online backups in our system used to complete in max of 1 hour.But now the same backup is taking around 7 hours.

Can any body suggest me how to find out the why it is taking this much time.

Thanks in advance.

Regards,

Chandra.

[Former Member]

Thanks.

[markus_doehr2]

A number of reasons can be the cause for this.

Are you backing up locally or remotely to a backup server?

Are you running multiple backups at the same time to the same device?

Are you working on SAN that is maybe heavily loaded at that time?

--

Markus

[Former Member]

Hi Markus,

We are taking backup locally on the same system and no other backups running.

and coming to3rd question I am not aware of SAN.

Regards,

Chandra.

[markus_doehr2]

I mean the harddisk.. are there any jobs running that put a heavy load on the system? Did you change something in the configuration (HP-UX kernel, br*tools configurations) prior to the reboot?

I can just ask those question since your questions is very generic and you didn´t describe how you backup (backup software?), what´s the hardware behind etc.

--

Markus

[Former Member]

Hello Markus,

I dint find any jobs running at the time of backup from SAP side.

And we are taking the backup locally(I mean on the hard disk).

And coming to HP-UX kernel, br*tools configurations changes,I have no Idea how to check the changes.Please help me in finding this.

And about ackup software we are using the sap tools for taking backups(BR*Tools).

Please reply if you require any more information.

Regards,

Chandra

[markus_doehr2]

If you back up to the harddisk, are those disks the same the database itself resides on?

there is not a real way to track changes in the BR*TOOLS configuration if you don´t use something like cvs or write it down manually.

What tool do you use - cpio or dd to backup to the tapes?

--

Markus

[Former Member]

Hello Markus,

The backup which we are taking is on the same disk where the database resides.

As of my knowledge cpio is used for compression.And I don't know about dd.

And there is no tape backup as mentioned above(we are taking on the disk).

Regards,

Chandra.

[markus_doehr2]

Ok...

If you put the backup on the same disks, it puts a HIGH load on those disks, because they need to read and write at the same time, this is certainly one slowdown factor.

I suggest switching to "dd" as backup tool instead of cpio, it can use bigger blocksizes and thus make backup faster.

--

Markus

[Former Member]

Hello Markus,

I don't know how to switch the backup to 'dd'.

Any way here are some more details from the detail log of the backup which may be helpful to you as well as me...

<b>BR0051I BRBACKUP 6.40 (15)

BR0055I Start of database backup: bdvysiww.and 2007-08-19 23.23.38

BR0477I Oracle pfile /oracle/RQ1/920_64/dbs/initRQ1.ora created from spfile /oracle/RQ1/920_64/dbs/spfileRQ1.ora

BR0319I Control file copy created: /oracle/RQ1/sapbackup/cntrlRQ1.dbf 26320896

BR0101I Parameters

Name Value

oracle_sid RQ1

oracle_home /oracle/RQ1/920_64

oracle_profile /oracle/RQ1/920_64/dbs/initRQ1.ora

sapdata_home /oracle/RQ1

sap_profile /oracle/RQ1/920_64/dbs/initRQ1.sap.dail

backup_mode ALL

backup_type online

backup_dev_type disk

backup_root_dir /dailybkprq1

compress no

disk_copy_cmd copy

cpio_disk_flags -pdcu

exec_parallel 8

system_info rq1adm/orarq1 itdrq1 HP-UX B.11.23 U ia64

oracle_info RQ1 9.2.0.6.0 8192 58296 466337114

sap_info 640 SAPRQ1 RQ1 L0388554515 R3_ORA 0020223281

make_info hpia64 OCI_920 Oct 9 2004

command_line brbackup -u / -c force -t online -m all -p initRQ1.sap.dail -a -c force -p initRQ1.sap.dail -sd

BR0116I ARCHIVE LOG LIST before backup for database instance RQ1

Parameter Value

Database log mode Archive Mode

Automatic archival Enabled

Archive destination /oracle/RQ1/oraarch/RQ1arch

Archive format %t_%s.dbf

Oldest online log sequence 58293

Next log sequence to archive 58296

Current log sequence 58296 SCN: 466337114

Database block size 8192 Thread: 1</b>

Regards,

Chandra

[former_member204746]

change /oracle/RQ1/920_64/dbs/initRQ1.sap

parameter:

tape_copy_cmd = dd

this will certainly improve your backup time.

[Former Member]

Thanks you for the reply.

Would you please tell me in detail where we will get the difference by using cpio and dd.

Regards,

Chandra.

[former_member204746]

Markus answered you.

the blocksize is different and DD is faster because of big blocksize.