Odd slow throughput issue SAN backup

All,

I need some help..I've tried everything and my next step is to call Symantec.  I have a blade server connected to an LTO 3 HP tape blade.  I use BE11D 7170 and backup two 900 Gig partitions that are on a SAN.  The SAN is an HP EVA connected via Fibre.  My 1 partition will backup in 10 hrs with a 1.5 GB throughput...that rocks!  My other partition is running at 250-330 Meg/min and is taking about 50 hours to run!  I cannot for the life of me figure out why.  I've tweaked every backup setting I can think of..nothing helps.  Now granted, the partition in question has more smaller files, but, I find it hard to belive it can take four to five times longer to backup.    From the backup job log there are 2.8 million files/122,500 directories compared to the faster job which has 750,00 files/ 20,000 directories. 

I checked and neither partition needs a defrag.  Is there anything I can check as to why performance is sooo slow.  At one time in the past both jobs ran the same amount of time..not sure what has changed.

Damian

4 Replies
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Re: Odd slow throughput issue SAN backup

Well masses of smaller files WILL backup slower than fewer large files, but a five times factor does seem a little extreme

 

Don't have any suggestions for you though, sorry

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Re: Odd slow throughput issue SAN backup

O.k...this weekend I go the job to 700 Meg/Minute and it finished in 21 hrs.  I ran a 'quick erase' on the tape first.  Has anyone else ever seen this before.  I can't see how the erase would have speeded up the time from 50+ hrs to 21.  But, this is how fast it ran months ago. 

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Re: Odd slow throughput issue SAN backup

O.k..for 2 weeks the throughput doubled and the backup times were better.  This week, back to taking forever to run.  1TB partition with lot of files took 48 hrs to run..350 Meg/Minute.  Last week throughput showed 700 Meg a minute.  My other 1TB partion with less files took 12 hrs to run at 1200 Meg/minute, but, last week that ran at 2500 Meg/minute.  Anyone have any ideas????  I see nothing changed on our infrastructure side.  I have no idea if this issue is with the software or our hardware/network.

Damian

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Re: Odd slow throughput issue SAN backup

Hi Damian,

Did you eventually find out why your backups were going slow ? Or did u find some way of reducing the backup time.

 

I have a similar scenario what 1.2TB with 2million files is taking over 24hrs to backup.

 

thanks