Re: DBV slow W2K server

On 6/1/06, Christo Kutrovsky <kutrovsky.oracle_at_gmail.com> wrote:
>
> Average speed 30 Mb/sec. It's relativelly low, unless you are coping
> from 1 spindle to the same spindle.
>
> What version of Oracle ? Have you tried RMAN ? If the storage behind
> is an array I think you will be surprised by the speed improvements.
> That is if you have "filesystemio_options" set to "setall".
>
> --
> Christo Kutrovsky
> Senior Database/System Administrator
> The Pythian Group - www.pythian.com
> I blog at http://www.pythian.com/blogs/

Christo,

In what units do you measure a T1 line?
If you answer Mbps, you are correct. (Mega bits per second). A T1 line is capable of 1.54 Mbps. Those are bit bits, as in ones and zeroes.
For those of you that can recall using an external serial modem with blikenlights

In what units do you measure file transfer on hard drives via SCSI? If you answer MB/sec, you are correct again (Mega Bytes per second).

Imagine if you have an iSCSI implementation, where the hard drives have the capability to transfer data measured in customary units of MB/sec over ethernet that has the capability to transfer data measured in customary units of Mbps (10 Mbps, 100 Mbps, 1000 Mbps = 1 Gbps).

This isn't just like the hard drive vendors measuring storage capacity in powers of 10 rather than powers of 2, we're talking an order of magnitude here.

Vendor: "This SATA II iSCSI unit can support sustained throughput of 4 x 40 MB/sec, or 160 MB/sec."
Vendee: "But its connected over gigabit ethernet. Can't that only support 1 Gbps".
Vendor: "Uh, yeah, trunk it and we'll sell you another iSCSI accellerator. It has 2 ports."

I think that the custom of expressing hard drive throughput with a unit of small Bee "b" must be driven out of existence immediately and retroactively, lest we crash into the surface of the planet Mars or end up with actual throughput an order of magnitude slower than is desired.

Paul

On 6/1/06, O'Neill, S. (Seán) <Sean.oneill_at_organon.ie> wrote:
> > Use XCOPY to copy files disk-to-disk. Takes approx 80 minutes to copy
> files (147GB). 2GB RAM.
> >
> > -----Original Message-----
> > From: Christo Kutrovsky [mailto:kutrovsky.oracle_at_gmail.com]
> > Sent: 01 June 2006 14:08
> > To: O'Neill, S. (Seán)
> > Cc: Sriram Kumar; List, Oracle-l Freelists
> > Subject: Re: DBV slow W2K server
> >
> >
> > So how do you backup your files ? Windows copy ?
> >
> > If you are doing that, you are totally trashing your windows cache. I am
> not sure how big your system is (db size/RAM size) but I would guess that
> during the backup it's not performing that good ?
> >
> >
> > On 6/1/06, O'Neill, S. (Seán) <Sean.oneill_at_organon.ie> wrote:
> > >
> > > Hi Sriram,
> > >
> > > The particular DB has an offline backup taken each night Mon - Fri.
> > > This is done on a disk-to-disk basis. I was simply running the DBV on
> > > the backed up files as an extra check to verify if any corruption was
> > > present in files. We've not moved to RMAN (yet!). The AV settings are
> > > as they always were on the drive in question, i.e. excluded.
> > >
> > > - Seán
> > >
> > > -----Original Message-----
> > > From: Sriram Kumar [mailto:k.sriramkumar_at_gmail.com]
> > > Sent: 01 June 2006 12:50
> > > To: O'Neill, S. (Seán)
> > > Cc: List, Oracle-l Freelists
> > > Subject: Re: DBV slow W2K server
> > >
> > > Hi Sean,
> > >
> > > As pointed out by gurus it doesn't make sense to run a DBV on
> > > DB/Backup on a daily basis for a DB that is big in size. you can try
> > > to schedule the DBV may be once in a week/fortnight/month(off peak
> > > time when nothing else is
> > > running) as a proactive measure.
> > >
> > > I assume you are not using RMAN for DB backup.I dont know the size of
> > > your DB/backup and hence comment on the time taken for the DBV.
> > >
> > > Being a Windows Box, I am to ask you an basic question. Is by any
> > > chance the Virus Scanner is enabled on the area where Oracle
> > > Datafiles/Backups are located?. If yes this could slow down things and
> > > may be you can configure the VS to ignore these areas.
> > >
> > > Best Regards
> > >
> > > Sriram Kumar
> > >
> > >
> > >
> > > On 5/30/06, =?iso-8859-1?Q?O'Neill_at_freelists.org <=?iso-
> > > 8859-1?Q?O'Neill_at_freelists.org> wrote:
> > > > Hi Folks,
> > > >
> > > > Would appreciate some help/guidance with an issue I've noticed with
> > > > the
> > > dbv utility on Windows 2000 server. I'm using this utility as part of
> > > an offline backup process. For some reason the dbv is now taking over
> > > 9 hours to complete. It used to take about half this time. I've been
> > > to Internet to try and track down if this is a known issue but to no
> avail. The Oracle
> > > manuals have not been much help either. I've looked at the server
> and it
> > > does not appear to be maxed out by anything that would cripple the dbv
> > > executing.
> > > >
> > > > Regards,
> > > > - Seán O' Neill
> > > > --
> > > > http://www.freelists.org/webpage/oracle-l
> > > >
> > > >
> > > >
> > >
> > >
> >
> >
> > --
> > Christo Kutrovsky
> > Senior Database/System Administrator
> > The Pythian Group - www.pythian.com
> > I blog at http://www.pythian.com/blogs/
> >
>
>
> --
> Christo Kutrovsky
> Senior Database/System Administrator
> The Pythian Group - www.pythian.com
> I blog at http://www.pythian.com/blogs/
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

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you must first start with a normalized design."
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