SAP Mix

RE: Ontape remote tape backup performance ...

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Date:

Hi Keith,

Its IDS 7.31UD2XG. I think our release already included the fix for that
bug. I will check it out anyway.

Thanks
Rajesh Rajasekaran
Informix Database Administrator
Forest Pharmaceuticals Inc.
314-493-7073 (Work)
314-662-6619 (Cell)
314-514-2457 (Home)


-----Original Message-----
From: Simmons, Keith [mailto:keith.simmons@bbslimited.co.uk]
Sent: Tuesday, February 04, 2003 10:11 AM
To: 'Rajasekaran, Rajesh'
Cc: 'informix-list@iiug.org'; 'sapmix@iiug.org'
Subject: RE: Ontape remote tape backup performance ... [32]


Rajesh

***** PLEASE DON'T POST HTML *****

What version of Informix?
Could you be hitting Very Old Page Bug?
We have found a level 1 can take as long as a level 0 on a heavily used
machine.
Just some thoughts.

Keith

-----Original Message-----
From: Rajasekaran, Rajesh [mailto:RRajasekaran@forestpharm.com]
Sent: Tuesday, February 04, 2003 3:38 PM
To: 'informix-list@iiug.org'
Cc: 'sapmix@iiug.org'
Subject: FW: Ontape remote tape backup performance ... [32]


Hi,
I checked the network data transmit rate for a FTP transfer. It sends data
of 215 MB/hour approximately. Our level 1 backup size for this box is
around 1.5 GB.Whatever network delay happens, it should have completed by 10
hrs at the max. But it takes 45 hrs to complete just the level-1 backups.
Just to recollect, We have done the same remote tape backups when this box
was in the same building and the level-1 took only 2 hrs. Considering our
network throughput, I expect the backup delay but not to the extent of 45
hrs. Since Level-1 spends most of the time doing disk reads within the box
when compared to data transfer thru the network, i am wondering why it takes
so much time on reading.
I would like to clarify the following doubts.
1) Do we have to fine-tune OS kernel parameters for remote tape backups like
more buffers etc.?
2) I could see the "onstat -g ioq" maxlen shows upto 70 during the backup
run. I guess its normal during the backups.
3) I would like to fine-tune OS/database if the backup delay caused within
the box. Please pass on your suggestions.
4) Apart during data transfer during level-1, Does ontape communicates with
the network for some reason even while performing disk reads which
cause the delay ?
Thanks
Rajesh Rajasekaran
Informix Database Administrator
Forest Pharmaceuticals Inc.
314-493-7073 (Work)
314-662-6619 (Cell)
314-514-2457 (Home)

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Messages In This Thread

• RE: Ontape remote tape backup performance ...
  -- Tuesday, 4 February 2003, at 11:16 a.m.

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