Veritas-bu

[Veritas-bu] 2 tape drives issue

2003-03-14 06:00:40
Subject: [Veritas-bu] 2 tape drives issue
From: dbase77 AT yahoo DOT com (Feroz F. Basir)
Date: Fri, 14 Mar 2003 11:00:40 +0000 (GMT)
Hi,

By default netbackup pickup H/W compression. I checked
on the config file. I suppose my buffer size that
cause this extra time. I'm going to run another test
backup now with new buffer size and see if I can
improve the time. I'll let everybody knows the result.

How do I check if my backup using the new buffer
setting? any log file I can view. The doc saiod bptm
log. Icouldnt find it on my system though.

Thank you to all of you for giving me some guideline.

regards,
feroz

 --- "Donaldson, Mark"
<Mark.Donaldson AT experianems DOT com> wrote: > Drive
compression, in Unix, is controlled by the
> major & minor numbers
> associated with the device files.  These major &
> minor numbers, are
> therefore referenced by the filename. 
> 
> For solaris, look for the /dev/ entry for your
> drives ending in "cbn", ie:
> /dev/rmt/0cbn.  The "c" in "cbn" stands for
> "compressed".  If you use that
> name in your storage unit setup (tpconfig -l), you
> should get compression at
> the drive.
> 
> Yes, I'd definitely increase the 32K to at least 128
> & maybe 256K.  Don't
> screw with the number of buffers unless you're not
> getting sufficient
> throughput - both changes can increase memory usage
> so tweak them up slowly.
> The LTO drive wants big blocks of data for better
> throughput & compression.
> Feeding it 32K teaspoonfuls will starve it.
> 
> Using both drives will speed backup times but you
> have to plan for it in
> policy creation, storage units, pre- & post-schedule
> jobs, etc.  I backup
> nearly 350G of oracle data nightly (direct scsi, no
> network) using four
> streams to two DLT drives (7-8 MB/sec max).  It
> takes about 6.5 hours.  I
> use a NUMBER_DATA_BUFFERS of 64 and
> SIZE_DATA_BUFFERS & NET_BUFFER_SIZE of
> 262144 (256K).
> 
> HTH - Mark
> 
> -----Original Message-----
> From: Feroz F. Basir [mailto:dbase77 AT yahoo DOT com]
> Sent: Thursday, March 13, 2003 10:27 AM
> To: Donaldson, Mark;
> veritas-bu AT mailman.eng.auburn DOT edu
> Subject: RE: [Veritas-bu] 2 tape drives issue
> 
> 
> Hi,
> 
> Thank you for replying. How do I go about turn on
> the
> LTO drive compression, as these drives are attach to
> L25 tape library at the back. Any command I can use?
> I
> also going to uncheck the netbackup compression see
> how it goes tonite. Regarding the buffer setting,
> I'm
> using the default which I think 32K. Do you think
> this
> buffer setting cause the extra time? I attached the
> tape library to our SUN box and ONLY backup data
> from
> the SUN. No network backup or so ever. I'm very
> suprise about the time that I have here.
> 
> What negative impact can I get if I use bigger
> buffer
> size? And if I use both drives at the same how's the
> writing work? Does it write at the same time or one
> after another?
> 
> I'll let you know the outcome tomorrow morning.
> 
> Thank you.
> 
> regards,
> feroz
> 
>  --- "Donaldson, Mark"
> <Mark.Donaldson AT experianems DOT com> wrote: > Don't use
> the Netbackup client compression.  It's
> > software based and causes
> > a high client load, slowing the backups.  Your LTO
> > drive is capable of
> > hardware compression, use that.
> > 
> > LTO is good for about 15 MB/sec native, perhaps
> > 25-30MB streaming rates if
> > you can get the data to it fast enough & the data
> is
> > decently compressible.
> > So 74G at 15 MB/sec is only 84 minutes so you're
> > really underperforming. 
> > 
> > Check your buffer sizes.  For my LTO drives, I'm
> > using 256K buffers & it
> > makes a big performance difference.  Check this
> > whitepaper for a description
> > buffer sizes & counts.  Make sure to set the
> buffers
> > for both client & media
> > server. 
> > http://seer.support.veritas.com/docs/183702.htm 
> If
> > your system is
> > Windows, check out this instead:
> > http://seer.support.veritas.com/docs/244652.htm
> > 
> > Also consider the path from client to media
> server. 
> > If it's standard
> > ethernet, it's only capable of about 10MB/sec, and
> > your drive will be
> > underutilized.  Consider Gigabit ethernet if
> > possible.
> > 
> > That should be enough to start with - post back
> any
> > results you get.
> > -M
> > 
> > -----Original Message-----
> > From: Feroz F. Basir [mailto:dbase77 AT yahoo DOT com]
> > Sent: Thursday, March 13, 2003 9:54 AM
> > To: Donaldson, Mark;
> > veritas-bu AT mailman.eng.auburn DOT edu
> > Subject: RE: [Veritas-bu] 2 tape drives issue
> > 
> > 
> > Hi,
> > 
> > LTO drive.
> > 
> > regards,
> > feroz
> > 
> >  --- "Donaldson, Mark"
> > <Mark.Donaldson AT experianems DOT com> wrote: > What
> kind
> > of
> > drive (DLT, LTO, etc.) in the L25?
> > > -M
> > > 
> > > -----Original Message-----
> > > From: Feroz F. Basir [mailto:dbase77 AT yahoo DOT com]
> > > Sent: Thursday, March 13, 2003 4:15 AM
> > > To: veritas-bu AT mailman.eng.auburn DOT edu
> > > Subject: RE: [Veritas-bu] 2 tape drives issue
> > > 
> > > 
> > > Hi,
> > > 
> > > Thank you to all who replied to my problem. I
> got
> > it
> > > to work to use both tape drives at the same time
> > > using
> > > 2 different policies. 
> > > 
> > > Backup took about 5 hrs to finish for 74 GB data
> > on
> > > 1
> > > tape. I wonder myself if I can improve the time
> > > here.
> > > I only backup oracle data files. Plus select to
> > > compress. Is this normal behaviour. I'm using NB
> > 4.5
> > > business server on SUN storedge L25 tape library
> > > with
> > > 2 drives.
> > > 
> > > Thank you again.
> > > 
> > > regards,
> > > feroz
> > > 
> > >
> __________________________________________________
> > > Do You Yahoo!?
> > > Everything you'll ever need on one web page
> > > from News and Sport to Email and Music Charts
> > > http://uk.my.yahoo.com
> > > _______________________________________________
> > > Veritas-bu maillist  - 
> > > Veritas-bu AT mailman.eng.auburn DOT edu
> > >
> >
>
http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu
> > >  
> > 
> > __________________________________________________
> > Do You Yahoo!?
> > Everything you'll ever need on one web page
> > from News and Sport to Email and Music Charts
> > http://uk.my.yahoo.com
> >  
> 
> __________________________________________________
> Do You Yahoo!?
> Everything you'll ever need on one web page
> from News and Sport to Email and Music Charts
> http://uk.my.yahoo.com
> 
=== message truncated === 

__________________________________________________
Do You Yahoo!?
Everything you'll ever need on one web page
from News and Sport to Email and Music Charts
http://uk.my.yahoo.com