Networker

Re: [Networker] Performace isssues with LTO 2 Ultrium and unable to write to all tapes at same time

2004-01-11 15:11:03
Subject: Re: [Networker] Performace isssues with LTO 2 Ultrium and unable to write to all tapes at same time
From: Alex Theodore <alex AT FUZZYCHEESE DOT COM>
To: NETWORKER AT LISTMAIL.TEMPLE DOT EDU
Date: Sun, 11 Jan 2004 15:12:21 -0500
I tried local backups and I get the same story 3-6 mb/s.

The L700 is connected SCSI configuration is like so:

  - 2 drives per scsi bus (X6541  Dual Differential Ultra/Wide SCSI - pci) thus 
3 controllers

I'll look into the whole i/o contention theory with the nsr db by using iostat 
on the box while backing it up.

Thanks,

  Alex

On Sun, 11 Jan 2004 12:45:57 -0500
Paul Galjan <pgaljan AT YAHOO DOT COM> wrote:

> I don't know if you're going to be able to get the advertised 180 MB/s  for
> all six drives.  But the place to start would be to see if you can get
> anywhere close to that rate backing stuff up without going over the network.
> See if you can write two data streams at 30 MB/s each, step it up from
> there.  See when it breaks.
>
> Another area to check would be to make sure that you are effectively load
> balancing over both the NICs.
>
> Yet another suspect would be the Networker database.  You've got a partition
> with 3 MB files, so each drive should be backing up 10 records per second.
> That 60 inodes per second, each updating the database.  I'm no Networker
> database expert, so I can't say for sure if the software can handle that
> (perhaps someone on this list can), but you can definitely tell if it's a
> hardware bottleneck.
>
> How is the SCSI bus configured (how many channels are the drives spread
> over?).
>
> --paul
>
>
> ----- Original Message -----
> From: "Alex Theodore" <alex AT FUZZYCHEESE DOT COM>
> To: <NETWORKER AT LISTMAIL.TEMPLE DOT EDU>
> Sent: Sunday, January 11, 2004 11:19 AM
> Subject: [Networker] Performace isssues with LTO 2 Ultrium and unable to
> write to all tapes at same time
>
>
> > I am only getting about 3-6 megabytes/s when backing up to LTO 2 tape
> drives.  I would expect that I should get somewhere near the advertised
> value, but I am not.  Here are the details.
> >
> > - Legato Network 6.7.1
> > - Solaris 8 (latest patches)
> > - Sun L700 with 6 HP LTO 2 tape drives
> > - Backup Server is a Sun Fire V880
> > - Backup Client is Sun Enterprise 4500
> > - Network pipe for backups is a dedicated, directly connected (no switch),
> dual gigabit ethernet, which is trunked (glued together into 1 virtual pipe)
> >
> >
> > The data on the client which is being backed up are images (photos) which
> are a few megabytes in size.  I decided to split up the save sets into 6
> different client configurations with the parallelism set to 6 so that all 6
> tape drives would be used at the same time during backups but this isn't
> happening either.. I can only seem to write to a few tape drives at once..
> >
> > Any ideas would be greatly appreciated.
> >
> > TIA,
> >
> >   Alex
> >
> > --
> > Alex Theodore
> > alex AT fuzzycheese DOT com
> > Boca Raton, FL  USA
> >
> > --
> > Note: To sign off this list, send a "signoff networker" command via email
> > to listserv AT listmail.temple DOT edu or visit the list's Web site at
> > http://listmail.temple.edu/archives/networker.html where you can
> > also view and post messages to the list.
> > =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
>
> --
> Note: To sign off this list, send a "signoff networker" command via email
> to listserv AT listmail.temple DOT edu or visit the list's Web site at
> http://listmail.temple.edu/archives/networker.html where you can
> also view and post messages to the list.
> =*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
>


--
Alex Theodore
alex AT fuzzycheese DOT com
Boca Raton, FL  USA

--
Note: To sign off this list, send a "signoff networker" command via email
to listserv AT listmail.temple DOT edu or visit the list's Web site at
http://listmail.temple.edu/archives/networker.html where you can
also view and post messages to the list.
=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=