Throughput - What should it be?

[amacqueen]

Can anyone give some guidence with respect to the mb per minute that Arcserve should be delivering. Here are the installation specifics:

Dell Powervault 120T DDS4 external connected to Adaptec 29160.

Server is Dell 1400SC 1ghz with 1gb of memory
Local backup is off a Dell PERC with 128mb cache

Remote backups are over switched 100mbs off of 1ghz machines

My local backup seems to peak at about 180-200mb per minute. Remote backups are about the same.

Also have Exchange 2000 agent, throughput on Info Store is 160mb/minute on about 5 gig. Brick level is about 50mb/minute on about 4.1 gig.

Do these rates seem about right or are they low which might indicate a configuration problem?

All comments appreciated.

Thanks
amacqueen

 

[databasebaba]

Hope this helps

apply the sp4 to ARCserve and Exchange agent
apply QO20824.CAZ to ARCserve alone &
QO22840.CAZ to Exchange agent

http://support.ca.com/Download/patches/asitnt/arc_eng_menu.html

Try this out if you still have a problem we have more options to go.

Update us about the status
DatabaseBaba

 

[amacqueen]

Sorry forgot to add that I am running Arcserve 9. However, prior to the upgrade, I was getting similar throughput and had already applied the patches you suggested.

Other suggestions?

amacqueen

 

[speshalyst]

The throughputs look OK... trying to trouble shoot it might
take adverse effects and might bring it down..

Id say it is best left as it is..

cheers
speshalyst So it Shall be Written!
So it Shall be Done!!

 

[amacqueen]

Ok. If that is the case then here is my issue. My current backup process runs from 6pm to about 4am. Exchange IS and Brick takes about two of those hours. I am planning to dramatically increase my exchange system storage so if the current throughput stays the same, the exchange backup could take as much as 4 to 5 hours in the near future. What can I do to shrink my overall backup window for the entire job or at least the other non-exchange parts of the job. I have seen other posts with people getting some really big numbers which would be great. Ideally, I would love the have the backup finished after 6 to 7 hours which would leave additional time at night for other tasks.

Thanks in advance for all you suggestions and help.

amacqueen

 

[NorbertNetzwerk]

Your problem is not a technical one afa ARCserve is concerned. Your backup is already running at the maximum speed this tape technology will allow.
Solution: upgrade to a different tape technology (i.e. drive):

format     vendor   capacity (GB) MB/sec GB/h
DDS-4      HP       20            3      10.5  
DLT1/VS80  Tandberg 40            3      10.5  
VS160      Tandberg 80            8      28.1
DLT8000    HP       40            6      21.1
SDLT220    Tandberg 110           11     38.7
LTO        IBM      100           15     52.7
SDLT320    Tandberg 160           16     56.3

Notes:
1. vendor listing is not complete, usu. there are far more offering the same technology
2. all capacity and throughput figures are cited without compression. Add 20 to 100% for real figures but do not speculate on this.
3. DDS is deemed being quite unreliable. Enjoy getting rid of it.
4. ARCserve may need a registry tweak to achieve high throughput with faster tape drives, noteably DLT and LTO.

IMHO the new VS160 is very attractive: safe (DLT format), high capacity, very fast, and costing far less than the "enterprise" solutions SDLT and LTO.

Keeps us informed.

HTH, NorbertNetzwerk

 

[rowster]

You could always benchmark the hardware using the technique below and then compare against actual results...

let me know how it goes..

Use this procedure to turn on dummy tape drives to test system throughput without using a real taoe drive (i.e. the maximum speed that could be expected through network and/or local hard disc speeds):
Stop the Tape engine
Go to Command Prompt ,change the directory to Arcserve
cd program files\ComputerAssociates\Arcserve.
type the following command "simulate -ca"
select the option to add simulation device .
Number of Boards =1
Number of devices to simulate=1
exit
Start the Tape engine
Erase the media on the tape simultation device then ubmit a backup job to it.

 

[NickFerrar]

I'd stick the DAT device in another server and have that do the remote backups. In the Exchange server but a DLT1 drive (or LTO if you have plenty of money and performance is really critical). We generally get about 300-400MB per minute on a local DLT backup. We don't do brick level Exchange backups due to the overheads, we've made our users aware of this (we retain 30 days of deleted items on the Exchange server anyhow) and it hasn't been an issue so far. We've only done one Exchange restore and that was a full restore when we changed the hardware it was running on.

Do you really need to do brick-level for each user? If not I'd just do it for the senior management after consultation...