Link to home
Start Free TrialLog in
Avatar of gregmiller4it
gregmiller4itFlag for Australia

asked on

slow backup to usb hard disk

My customer has an SBS 2003 SP2 server and uses SBS backup to backup to 5x USB hard drives, one for each day of the week. They use digital imaging in their accounting practice, so the data set is steadily growing and the backups are taking longer.
The current backup starts at 9pm and finished this morning around 5am. Last night's backup of 22GB from C: took approx 3hr 30mins and 77GB from D: took approx 3hr 45mins. This works out at approx 1.7MB/s for C: and 3.75MB/s for D: and an average of approx 3.8MB/s.
I believe that USB 2.0 hard drives should be able to realistically manage around 30MB/s and this backup is no where near that.
I have viewed Device Manager 'by connection' to make sure that the USB hdd is connected to the Enhanced USB controller. I have hacked bkrunner.exe to turn off the verify option and edited the  SBS Backup User's NTUSER.DAT file for some performance tweaks. Both of these ideas came from the following link:
http://blog.chrisara.com.au/2007/09/modifying-sbs-2003-sp1s-bkprunnerexe.html
The above mods has improved things dramatically - previously the backup wasn't finishing until after 11am the next day.
But it seems that the drives are not running anywhere near their best speed.
Does anyone have any ideas how I can help the situation?

Cheers,
Greg
Avatar of dekkar
dekkar

How many files are you backing up?


Speed can be drastically effected if you are backing up lots of smaller files. Rather than say files that are 1gb in size.


Have you tried moving external drives to another machine and see how long an equal amount of data takes to move. It could help you figure out whether the issue is the system or the drives.
Suggest you replace the USB solution with eSATA solution.

Look at the DAT Optic eBOX-R5 is a high performance five Serial-ATA (SATA) drives hardware raid enclosure built-in PM ware, it offers a stand alone RAID system, that independent from OS such as MAC, Windows, Linux and Novell OS.

http://www.datoptic.com/hardware-raid-5-enclosure.html

With a SATA / eSATA port on a system and our eBOX-R5, end user can now have a fast, protected, massive (up to 10TB) volume that transfer 230MB/sec ~ 250MB/sec sustain rate, that requires NO DRIVER.  eBOX-R5 is eliminated host CPU loading by using the embedded RISC storage processor.

Has 5 drives trays, can be configured as RAID 1, 5, or JOBDs.  They sell PCIe or PCIx eSATA cards and hard drives to match system.

I have one, works great and speed is fast.  This will dramatially shorten your backup time.
As BITCooler states ESata is considerably faster than USB.

Though even with USB, 22gig should not take 3.5 hours
Are you completely sure the host system is USB 2.0?
Avatar of gregmiller4it

ASKER

Dekkar,
The backup is done with SBS Backup, which is (apparently) just a wrapper for ntbackup. So, it is backing up lots of smaller files but actually saving it as one great big (97GB) bkf file.
AustinComputerLabs,
I haven't tried the drives on another PC, but I gues I might be able to simulate a backup of comparable size.
Connectex,
The Device Manager shows an "Intel 82801G (ICH7 Family) USB2 Enhanced Host Controller" which I believe is a USB 2.0 controller.
BitCooler,
I know that I can change the hardware to a faster option, but that is not the point. The hardware they have should (I think) work a whole lot faster than it is and I was hoping I can improve the performance with what they have at present.

Cheers,
Greg
ASKER CERTIFIED SOLUTION
Avatar of connectex
connectex
Flag of United States of America image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Avatar of Imran Saeed
Please try to install updated chipset drivers for your system.

whats the brand/model of your system and can provide specs?

what are the external hard disk drives specs?
Key questions still unanswered are, how many files?  What is the mean and median size of the files?
Windows is absolutely terrible at fetching small files for backup.  Each file generates a complete traversal of the directory tree from root to that file, and in addition to the small file itself, things like the complete directory path, file name, and all file attributes must be stored.

If these are 1K or 10K files, the problem is almost certainly the files themselves, and moving to a (theoretically) faster target won't speed the backup any more than you could push a shopping cart faster on a freeway than in a parking lot.

One way to check the source speed is to test the read speed in a simulated backup.  HP's got a tool that can do this; download Library and Tape Tools from http://h18006.www1.hp.com/products/storageworks/ltt/index.html and run the disk read test on the server being backed up.

I do agree that it might help to update all system drivers.
It is also a universally good thing when questions of backup performance come up to keep the disk defragmented.
agreed.... if you are backing up lots of small docs, its going to take longer....

As a test, are you able to change the destination to a local disk on the server (if you have space). and see how long it takes?

You could have a disk to disk option like this:

1.  Run the NT backup to a locally stored faster disk.

2. Copy the 97Gb file to USB.

I do something like this on my network as the backup we take overnight I want to save in a few locations. So we backup over night as quick as possible, then copy it to a tape, and other locations the next day.

Greg,

OK, back to your existing USB hardware backup issue.  Here are some considerations:

1) If files being backed up are small, and therefore not condusive to optimal speed under windows backup as suggested, why wouldn't all jobs from inception have been slow?  Based on what you said, backups were fine, then they got slow.  So unless the file sizes changed, I don;t see that as the issue, because if true, backup speed would have been an issue from the beginning.

2) How full is your USB backup drive?  If it is getting close to being full, that could be A reason for diminished performance. Reason, is, hard disk writes begin on the outter area of the disk platter.  As it fills up, writes are getting closer to the center of the disk.  Try putting an new USB disk in place to see if performance improves.

3) You could try to use a multithreaded file copy utility to test performance outside of the Windows backup software.  A good utility is RICHCOPY.  Take a look at this TechRepublic article which includes a download link to RICHCOPY.

http://www.techrepublic.com/blog/window-on-windows/how-do-i-use-richcopy-for-high-powered-file-copy-and-transfers/1210

I use RICHCOPY to copy files off my server onto a USB and eSATA disk, it works pretty well.
Connectex, it didn't occur to me until you mentioned it, that a defrag may not have been done for some time on this server.
After checking on this, it was determined that a defrag had not been done in living memory! Also, we realised that currently it is not so easy to find a window of opportunity to do a defrag on this server because the backup starts soon after staff finish and finishes after staff start the next day! I also discovered that defrag and backup overlap has drastic performance issues (no surprise here!).
But over the period of about a week I was able to get both drives defragged. Also, the tweaks that I made earlier (detailed in the initial post) did actually make a difference, but they did not take affect immediately...weird!!
Anyway, as a result of those tweaks and the defrags, the backup is now consistantly finishing at about 3am, so we have overcome our probhlem.
I am not sure that the USB drive is going as fast as it might be able to, but we have achieved what we needed to.
So, thanks to all...but Connectex gets the points!
Cheers,
Greg