How to Speed up the backup process

[Rao Uppuluri]

Hi
we have couple of oracle databases that we cold-backp (shutdown, backup,startup) every week night.
I am currently using "fbackup" and a DDS3 tape drive to backup.
The backup size is currently around 10GB and increasing. Backup now is taking about 2:30 hours and during that time my dbs are down. My question is,
Are there any other backup methods, softwares, hardwares etc. we can use to speed up this process??

TIA,
Rao

[Steven E. Protter]

Several methods depending on hardware and bucks.

If the database is on RAID 1 mirror, you can use lvsplit to break the mirror after database shutdown and then bring the database back up on the original.

You then copy the data off the mirror to a /backup filesysem.

While the database is up, you can rebuild the mirrors.

If you have lots of money, you can install a fiber card and use a Storage area network to run backups at a higher transfer rate.

If the backup is running through a NIC card, you can structure it so it runs on one machine, that increases throughput.

You can replace your dds3 tape drive with an Ultrium tape drive (around $5000) and get better tape througput via LVD SCSI.

SEP

[Stefan Farrelly · Accepted solution]

fbackup is still a good performance free tool to use, but your backup tape drive can be considerably increased - speed wise.

Upgrade options for it are;

DDS4
SuperDLT (much better than DLT4/7/8000)
Ultrium

We use the Ultrium drives as they are the quickest available and store huge amounts of data (over 400GB).

Fow now have your tried optimizing your backup with an fbackup config file - this can help a lot. Use it with the fbackup -c option. Heres what weve found to be the best options in our config file;

blocksperrecord 128
records 32
checkpointfreq 256
readerprocesses 4
maxretries 1
retrylimit 0
maxvoluses 1000

[Pete Randall]

Rao,

Assuming money is no object, I would have to recommend faster tape drives and a more robust backup software package, like OmniBack (or DataProtector - whatever they're calling it now).

Your dds3 drive does about 3.6 GB per hour according to specs and that looks about right given your 2.5 hour backup time. Switching to a DLT8000 drive would give you 21.6GB per hour, or roughly a 6X performance improvement. You can find DLT7000 and DLT4000 drives on the used market for reasonable prices and they will give you roughly a 4X and 2X performance gain, respectively.

The only thing with these faster drives is that you need the software, like OBII, to be able to provide data fast enough to keep the drive streaming. If you don't get enough data fast enough, the drives spend more time backing up and relocating than they do actually writing data.


Pete

[Jean-Luc Oudart]

I think most has been said.
Now, it goes back to the budget you would have/ you can get.
Hope people don't wait on major pb before they put money into backup.

We use OBII (sorry Data Protector).
We moved recently from DLT7000 (5 years !) to UltriumII for both speed and storage capacity.

Rgds,
JL

[A. Clay Stephenson]

Let me give you a Plan "C". First of all, no matter how fast your tape drives are they are never fast enough so you need to rethink the problem. You seem to want cold backups as opposed to an Oracle hotbackup which would incure zero downtime. A good compromise is to use OnlineJFS snapshot mount. You shutdown the database, snapshot the filesystem(s), and restart the database. Because the snapshot does not have to copy every block, the entire shutdown, snapshort, restart process usually is done in less than two minutes. You then backup the snapshots at your convenience and unmount the snapshots when done. You have all the safety and reliability of a cold backup with almost all the uptime of a hot backup. This is just one more reason that no HP-UX box should be without OnlineJFS.

[Chris Vail]

Get a faster tape drive. Others suggested SDLT, DDS4, Ultrium or LTO drives. These are all excellent choices. Let me also suggest you look at StorageTek and their 9940 or 9940B. These are probably the fastest drives around, but fabulously expensive. http://www.storagetek.com/pdfs/T9940B_DS_MT9188D.pdf

We use them here. If you can keep the fiber channel saturated with data (depends on RAM and CPU Mhz), you can backup your 10GB in under half an hour (prolly 10 minutes). The tapes are pricey also, at $90/each. We use them here, and are delighted at their capacity and speed. As in all things: you get what you pay for. This is one of the best tapes out there, so expect to pay a bunch.


Chris

[Don Spare]

Someone already mentioned using a SAN. We have an EMC Symetrix that we have configured to establish a BCV (business continuation volume(???)). Using this type of technology is similar to the mirror split described earlier. The BCV is simply another/additional mirror set that allow you to do the split without losing the RAID1 redundancy on your primary disks.

My configuration requires about 5 minutes total database down time and that is consumed by the process of shutting down the database, splitting the BCV and restarting the database. The BCV is synchronized just prior to all this but that does not effect DB uptime as it is done in background while everything is running. Then when the DB is shutdown, the BCV contains a consistent copy which is then backed up to tape after the BCV split.

Of course you have to have a setup similar to the EMC Symetrix or Clariion to do this. This can require some deep pockets to get going.

Good luck with your project.

[Bill Hassell]

As mentioned, the DDS3 is running at full speed so there is nothing that can be done to improve the current design. As mentioned, adding a backup mirror to your database would allow a very short (minutes) window of downtime and you could backup in the middle of the day from the split-off mirror.

Since DDS3 is fairly old technology, you may have a fairly old (and slow) CPU and disk setup, so jumping forward to something like a DLT 8000 or Ultrium tape drive may actually slow the backup to a crawl because your computer and disks cannot keep these very fast devices busy. Because they are streamers (like your DDS3), they must always have more data than they can use to keep moving at all times. Once the tape drive runs out of data due to a slow CPU and/or disks, the tape must be stopped, reversed, re-synced and start streaming again--which takes a long time (seconds) during which time the data backup rate is ZERO bytes per second.

So if you are running an E-series (E25, E35, etc), a D-series (D200, D350, etc) or a K-series (K100, K200, etc), your needs may have simply exceeded the capacity of the old hardware. A replacement rp-series computer will actually be cheaper than your original box yet run 3 to 8 times faster, and will support the high speed devices.

[Rao Uppuluri]

Thanks all for very useful explanations and solutions. After going through all the responses, I want to try a simple solution of, getting a new disk, like a 18gb, shutdown dbs, copy datafiles to the disk, startup dbs and backup the disk to tape. Saves me time and $s.
When we upgrade our L2000, should be soon, I can look for more robust solution. Thanks again for the responses.
Rao

[Camel_1]

Use a fast tape device ... DDS4, STK 9740 ...

Setup a enterprise backup environment and using GB network switch/interface.

[Douglass Anderson]

I used a -c option with the following settings and it was three times faster 5 Minutes rather that 15 Minutes for DLT backing up large files.

blocksperrecord 256
records 32
checkpointfreq 1024
readerprocesses 6
maxretries 5
retrylimit 5000000
maxvoluses 200
filesperfsm 2000