Poor backup performance

[Guest_imported]

Wow I'm glad I found this forumn as I have been quite frustrated with Legato (software and support).

Here is my scenerio:

We have a 330GB SQL 7 database on an EMC storage unit connected directly to a Compaq 7000 server (4 way, 2GB RAM) with two Emulex 8000 (64 bit) fibre cards. In turn the server is connected directly (no fibre switches) to an ATL P3000 (16 DLT 35/70 drives) through three Emulex 7000 (32 bit) fibre cards.

You would think this would backup that 330 gig database no prob But we are getting horrid performance trying to write to all 16 tape drives in the ATL using the SQL agent.

Does anyone have any performance tuning tips ? I'm thinking parallelism (spelling ?) Or should we dump the SQL agent and do a standard file system backup ? We are very close to dumping Legato all together.......

We have a "support" person on site who has not been much help......

Thanks for any help,
Raymond Brantley
System Administrator

 

[Guest_imported]

Hello,
I' m supposed that your ar using the NetWorker module to backup your MSSQL online.
Which parameters are you using for your client parallelisme ?
( to see it , use the display hidden attributes options)
You could try this parameters :
1 Use only eight drives
2 Clients parallelisme 8 for the MSSQL client
3 Drive parallelisme 1 per each on 8 drives.
Create a pool to backup the MSSQL which are using only this eight drive.

Test a backup and verify the speed of yours drives .
Sometimes it's better to decrease the parallelisme

Last thing , put the the server parallelisme at least to 8

Thierry

 

[mgdaviso]

Two things you can do:
Look at the performance tuning guide supplied with your legato installation pack on the documentation CD, or get it from

http://www.legato.com

or
dump legato - would probably be easier in the long run Mike davison
mike.davison@avon.com

 

[RBrantley]

Thanks to both of you for the suggestions, I will try them. I have downloaded the Performance Tuning guide and SQL agent guide also.


I wish I could dump Legato

I am definitely not a fan.


Thanks again,
Raymond Brantley

 

[Guest_imported]

Hi, when i first started with Legato i also had bad perfomance, but now i have tuned the system. I have a Compaq Taperobot with 6 DLT7000 tapedrives and i do a full backup off SAP/R3 (oracle) 1.1 TB in 5 hours.

My Backup server is a Digital with tru64 Unix

Thats Unix , if i try to backup a SAP/R3 running on an NT 4.0 Server and onto my backupserver i get only 6MB/s at the highest and down to 100 Kb/s. on Unix it is between 18MB/s and 10MB/s.