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#1 (**permalink**) 04-19-2008, 09:00 PM

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Alexey,

Our level-0 bkup on QAS is currently taking 10-11 hrs for the 400 =
GB
database with the serial backup and single stream. The level-1 bkup =
used to
take not more than 2 hrs to backup. Our PRD level-1 is still taking =
1-1.5
hrs and its storedge array is SUN 3510 FC array. Moreover on the QAS, =
I
dont think its the T3 array throughput bcos if thats the case, it would =
have
degraded the level-0 as well but its not. We dont take level-2 here. =
Iam not
suspecting the DLT drive too. Its somewhere btw the ONBAR & the IDS.

Let me check what else is changed on the box such as O/S patches, T3 =
disk
array related patches in the recent past.=20

More suggestions are greatly appreciated.

Thanks
RAJ

-----Original Message-----
From: Alexey Sonkin [mailto:alexeis@grandvirtual.com]
Sent: Thursday, April 08, 2004 5:19 PM
To: 'Rajasekaran, Rajesh'; 'sapmix@iiug.org'
Cc: 'informix-list@iiug.org'
Subject: RE: Incremental Archive performance issue......

Rajesh,

It's not clear to me from Your email how long it takes
to make the level-0 backup of Your QAS.
I suppose it is about the same as Your Level-1 backup.

Is Your question why You see such a significant difference between=20
level-1 and level-0 on PRD and no difference on QA?

During Level-1 backup, Informix is reading from the database
EXACTLY THE SAME amount of data as during level-0 backup.
For each page IDS makes timestamp comparison to decide, whether
to put that page into L1 backup or not. The only difference
between L1 and L2 is how much data the engine is sending to tape.

It means, that in Your case, on QAS backup performance
is limited by the T3 array throughput rather then by DLT limitations.
More powerful (I suppose) production disk array can ship data
much faster to IDS for analysis, and backup performance is constrained
by the DLT limitations...

------------------------------------------
Alexey Sonkin

=A0
-----Original Message-----
From: Rajasekaran, Rajesh [mailto:RRajasekaran@forestpharm.com]=20
Sent: Thursday, April 08, 2004 4:56 PM
To: 'sapmix@iiug.org'
Cc: 'informix-list@iiug.org'
Subject: Incremental Archive performance issue......

Hi,=20
=A0=A0=A0 Our QAS system is a Sun E450 box with a sun storedge T/3 =
array attached.
Its a solaris o/s with IDS 7.31 database. The DB size is around 400 GB. =
Its
backup is directed over the network to a tape library attached to a =
master
server which is another host. Our Master server is also the=A0 PRD box. =
Its a
Sun Fire V880 with Sun L40 tape libary attached. We have the Veritas
Netbackup Data center 4.5 for our backups & restores.
The QAS DB backup is going over the network to the master server's DLT =
tape
library that gives 35 GB/HR performance. We got that throughput for our =
QAS
level-0 bkup even though its over the T3 network. But the Level-1 =
backup has
severe performance degradation and it takes almost 5-7 hrs to complete. =
Our
PRD level-1's are taking anywhere btw 1.5 - 2 hrs.
We are only running the onbar whole system serial bkup. It should not =
put
much I/O bottlenecks since only one dbspace bkup is running at one time =
and
not parallel.=20
=A0I can see the iostat shows 10000-25000 Kb/sec for the T3 storedge =
array
continously during the level-1 bkups. The informix "onstat -g stq" =
shows
Full queue 0, Empty queue with Cnt 100 all the time. I dont see the I/O
bottleneck here and i dont see the problem with the Veritas Netbackup =
side
since our level-0 works as expected. I dont see any =
"arc_very_old_pages()"
running during the level-1 bkups.
Questions=20
1) What could be the reason for level-1 backup degradation in =
performance
when level-0 is performing well ?=20
2) What better way to monitor btw the onbar and the engine ? Will the
bar_dbug =3D 9 lvl trace shows=A0 more detail towards my problem ?
Any suggestions/comments is greatly appreciated.=20
=A0=20
Regards=20
Rajesh Rajasekaran=20
Informix Database Administrator=20
Forest Pharmaceuticals Inc.=20
(314) 493-7073=20

__________________________________________________ __________________ =20
This e-mail and its attachments may contain Forest Laboratories, Inc.
proprietary information that is privileged, confidential or subject to
copyright belonging to Forest Laboratories, Inc. This e-mail is =
intended
solely for the use of the individual or entity to which it is =
addressed. If
you are not the intended recipient of this e-mail, or the employee or =
agent
responsible for delivering this e-mail to the intended recipient, you =
are
hereby notified that any dissemination, distribution, copying or action
taken in relation to the contents of and attachments to this e-mail is
strictly prohibited and may be unlawful. If you have received this =
e-mail in
error, please notify the sender immediately and permanently delete the
original and any copy of this e-mail and any printout.

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Alexey,


      Our level-0 bkup on =
QAS is currently taking 10-11 hrs for the 400 GB database with the =
serial backup and single stream. The level-1 bkup used to take not more =
than 2 hrs to backup. Our PRD level-1 is still taking 1-1.5 hrs and its =
storedge array is SUN 3510 FC array.  Moreover on the QAS, I dont =
think its the T3 array throughput bcos if thats the case, it would have =
degraded the level-0 as well but its not. We dont take level-2 here. =
Iam not suspecting the DLT drive too. Its somewhere btw the ONBAR & =
the IDS.

 Let me check what else is changed on the =
box  such as O/S patches, T3 disk array related patches in the =
recent past. 


More suggestions are greatly appreciated.


Thanks
 RAJ


-----Original Message-----
 From: Alexey Sonkin [<A =
HREF=3D"mailto:alexeis@grandvirtual.com">mailto:al exeis@grandvirtual.com=
</A>]
 Sent: Thursday, April 08, 2004 5:19 PM
 To: 'Rajasekaran, Rajesh'; 'sapmix@iiug.org'
 Cc: 'informix-list@iiug.org'
 Subject: RE: Incremental Archive performance =
issue......

 
 

Rajesh,


It's not clear to me from Your email how long it =
takes
 to make the level-0 backup of Your QAS.
 I suppose it is about the same as Your Level-1 =
backup.


Is Your question why You see such a significant =
difference between 
 level-1 and level-0 on PRD and no difference on =
QA?


During Level-1 backup, Informix is reading from the =
database
 EXACTLY THE SAME amount of data as during level-0 =
backup.
 For each page IDS makes timestamp comparison to =
decide, whether
 to put that page into L1 backup or not. The only =
difference
 between L1 and L2 is how much data the engine is =
sending to tape.


It means, that in Your case, on QAS backup =
performance
 is limited by the T3 array throughput rather then by =
DLT limitations.
 More powerful (I suppose) production disk array can =
ship data
 much faster to IDS for analysis, and backup =
performance is constrained
 by the DLT limitations...

 

------------------------------------------
 Alexey Sonkin


=A0
 -----Original Message-----
 From: Rajasekaran, Rajesh [<A =
HREF=3D"mailto:RRajasekaran@forestpharm.com">mailt o:RRajasekaran@forestp=
harm.com</A>] 
 Sent: Thursday, April 08, 2004 4:56 PM
 To: 'sapmix@iiug.org'
 Cc: 'informix-list@iiug.org'
 Subject: Incremental Archive performance =
issue......


Hi, 
 =A0=A0=A0 Our QAS system is a Sun E450 box with a =
sun storedge T/3 array attached.
 Its a solaris o/s with IDS 7.31 database. The DB =
size is around 400 GB. Its
 backup is directed over the network to a tape =
library attached to a master
 server which is another host. Our Master server is =
also the=A0 PRD box. Its a
 Sun Fire V880 with Sun L40 tape libary attached. We =
have the Veritas
 Netbackup Data center 4.5 for our backups & =
restores.
 The QAS DB backup is going over the network to the =
master server's DLT tape
 library that gives 35 GB/HR performance. We got that =
throughput for our QAS
 level-0 bkup even though its over the T3 network. =
But the Level-1 backup has
 severe performance degradation and it takes almost =
5-7 hrs to complete. Our
 PRD level-1's are taking anywhere btw 1.5 - 2 =
hrs.
 We are only running the onbar whole system serial =
bkup. It should not put
 much I/O bottlenecks since only one dbspace bkup is =
running at one time and
 not parallel. 
 =A0I can see the iostat shows 10000-25000 Kb/sec for =
the T3 storedge array
 continously during the level-1 bkups. The informix =
"onstat -g stq" shows
 Full queue 0, Empty queue with Cnt 100 all the time. =
I dont see the I/O
 bottleneck here and i dont see the problem with the =
Veritas Netbackup side
 since our level-0 works as expected. I dont see any =
"arc_very_old_pages()"
 running during the level-1 bkups.
 Questions 
 1) What could be the reason for level-1 backup =
degradation in performance
 when level-0 is performing well ? 
 2) What better way to monitor btw the onbar and the =
engine ? Will the
 bar_dbug =3D 9 lvl trace shows=A0 more detail =
towards my problem ?
 Any suggestions/comments is greatly appreciated. =

 =A0 
 Regards 
 Rajesh Rajasekaran 
 Informix Database Administrator 
 Forest Pharmaceuticals Inc. 
 (314) 493-7073 

 
 
 

_______________________________________________ _____________________&=
nbsp;=20
 This e-mail and its attachments may contain Forest Laboratories, =
Inc. proprietary information that is privileged, confidential or =
subject to copyright belonging to Forest Laboratories, Inc. This e-mail =
is intended solely for the use of the individual or entity to which it =
is addressed. If you are not the intended recipient of this e-mail, or =
the employee or agent responsible for delivering this e-mail to the =
intended recipient, you are hereby notified that any dissemination, =
distribution, copying or action taken in relation to the contents of =
and attachments to this e-mail is strictly prohibited and may be =
unlawful. If you have received this e-mail in error, please notify the =
sender immediately and permanently delete the original and any copy of =
this e-mail and any printout.

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