Slow Flat File Backups

[H_Sharma]

Hello Experts,

We have 2 solaris clients that we have flat file backups and these take almost 12-15 hours to get completed due to very small files on the clients.

So do you recommend if we take multistreaming backups of these clients this would take less time and help us we can not go for flash backup.

But what about the I/O procressing of the client if we enable 4-5 streams per servers on the policy.?

Is there any performance issue on client?  

Pls help thanks so very much.

[sdo]

Hi Hargyan, multi-streaming could very well up running even slower in total / on average - due to even more disk thrashing.

1) Roughly how many files on each client?

2) What is the final average throughput on each?

3) What are the file systems?  (VxFS, ZFS, other?)

4) What version of Solaris (and patch level) on each client?

5) What version of NetBackup Client on each client?

6) Why can't you implement FlashBackup?

.

I ask teh questions above, because it may help me/us/others suggest some different options - but the options may vary depending upon the above - hence I ask the questions.  Thanks.

[revarooo]

You could implement msdp or accelerator or both. That may help. How many files are you talking about though?

[Marianne · Accepted solution]

From previous posts, it seems that only tape is used in this environment. Is that right? Also curious to know why FlashBackup is not an option? As far as multistreaming and multiplexing is concerned - this may work well if the filesystem is on a raid array. To know if there will be performance impact, I suggest that you start with 2 streams and monitor client resources while backup is taking place. If you are satisfied with the results, break up into 3 streams, then 4, and so on. When you get to a point where transfer rate is going down, go back to previous value. Only make changes to backup selection before a Full is due to prevent Incrementals running as full.

[sdo]

Hi Hargyan - have you tried the classic 'bpbkar to null' test - which will reveal just how fast the data comes up-from disk?  If this test is slow, then slow backups really is down to the file-system and/or paths to/from disk, and rules out anything to do with NetBackup Client LAN transport to Media Server and also rules out Media Server to target storage.

[H_Sharma]

Hi Sdo,

Thanks for help....

We never did not testing for bpbkar to null test. 

[sdo]

It's still not too late to run a bpbkar to null test.  Anything that helps you to narrow down the problem has got to be a good thing.  You should be able to find plenty of examples on this forum, as it is quite a popular topic.