RE: disk subsystem performance question

2002-04-11 Thread paquette stephane

I just started a couple days ago at this client. 
They're using Hitachi technology in the QA and prod
environment with 181G disk. I asked the SA twice and
he confirmed the 181 G disk.

I'll ask more details to the SA as soon as I know him
better.



 --- Deshpande, Kirti [EMAIL PROTECTED]
a écrit :  John,
  I agree with the 18GB drives implementation and
 pushing for more 'parity
 groups'. That's what we did. Now, HDS was back to
 sell more disk and backup
 soultions to us. I am not sure what we have agreed
 to purchase. A cache of
 10GB for the 400GB database is nothing. I bet you
 will have tables larger
 than the cache size. A single FTS on these tables
 will flush the whole
 cache... We have 16GB cache (I think I remember that
 right, and is the max
 for 7700E), and that is not enough for several
 servers that the cabinet
 supports. 
 
 - Kirti 
 
 -Original Message-
 Sent: Wednesday, April 10, 2002 7:08 PM
 To: Multiple recipients of list ORACLE-L
 
 
 
 Thanks for all the replies.  We are determined
 to lay out the data as
 well as we can across the disks we are about to
 purchase - with the goal of
 striping across array groups and smaller, faster
 drives. The real
 argument for us is 18GB vs. 73GB disk drives and how
 we can stripe. The
 Hitachi is configured into groups of 4 physical
 disks called parity
 groups and you can choose RAID 5 or RAID 1+0 for
 that 4 disk set.If
 you have 73GB drives in a 4-disk RAID 5
 configuration you get roughly 219GB
 of usable space in each parity group (this is what
 we are being told is the
 best option for us).This means our heavily
 concurrently accessed 400GB
 production database goes on 2 parity groups (2 sets
 of 4 disks).  To
 me, this sounds like a nightmare waiting to happen
 and we are trying to
 stop it.The 18GB drives are less capacity but we
 can get ourselves
 spread over more parity groups for better
 concurrency. We do have about
 10GB of cache but it is being shared across the
 enterprise with various
 other applications.  We as a DBA group are
 really trying to sell the
 18GB RAID 1+0 drive solution especially after
 reading the groups'
 experiences - unfortunately we are fighting a lot of
 marketing hype.
 
 If anyone has additional experiences or feedback
 with Hitachi or EMC they
 would like to share or comments (agree/disagree)
 with my thoughts, I'd love
 to hear them.   I'm open for learning!
 
 Thanks,
 
 John Dailey
 Oracle DBA
 ING Americas - Application Services
 Atlanta, GA
 
 
 
 
  
 
 Don
 
 GranamanTo:
 Multiple recipients of list
 ORACLE-L [EMAIL PROTECTED]   
 granaman@coxcc:
 
 .netSubject:   
  Re: disk subsystem
 performance question  
 Sent by:
 
 root@fatcity.
 
 com
 
  
 
  
 
 04/10/2002
 
 01:08 PM
 
 Please
 
 respond to
 
 ORACLE-L
 
  
 
  
 
 
 
 
 
 Short answer - NO!  Nobody's disk subsystem is so
 fast that no intelligence
 is required in the layout.  This is common vendor
 blather and one of the
 most popular myths.  I have been hearing it for at
 least six years - and it
 still isn't true.  Layout still makes a huge
 difference.  RAID levels still
 make a huge difference.  Cache won't solve all your
 problems (it does help
 though).  I've redone the disk layout on some of the
 biggest, fastest
 fully-loaded with cache EMC Syms available that had
 some don't worry about
 it layout and seen database throughput go up by as
 much as 8x.
 
 See Gaja's whitepaper on RAID at
 http://www.quest.com/whitepapers/Raid1.pdf
 .
 
 Don Granaman
 [certifiable oraSaurus]
 
 - Original Message -
 To: Multiple recipients of list ORACLE-L
 [EMAIL PROTECTED]
 Sent: Wednesday, April 10, 2002 10:38 AM
 
 
  Hi all,
 
  We are running both a Hitachi 7700E and a 9960
 disk subsystem here and we
  are getting ready to move our production DBs from
 the old(7700E) to the
  new(9960) Hitachi.  We have had trouble in the
 past on the 7700E due
 to
  disk contention and layout, i.e. we weren't
 striped across the array
 groups
  very well this caused pretty poor I/O
 performance.This has
 been
  a learning experience for the DBAs and the SAs
 here for the logical vs.
  physical aspects of our disks.  Anyway, to
 make a long story short,
 we
  are ordering disk for the move to the 9960 and we
 have 2 choices in disk
  sizes - 18GB and 73GB, and 2 choices in RAID - 1+0
 and 5. I would
 like
  to get the smaller, faster 18GB drives in a RAID
 1+0 configuration and
  stripe our data across the array groups as wide as
 possible. However,
 I
  am running into objections from the Hitachi people
 that their system is
  s fast we need not worry about such minor

Re: disk subsystem performance question

2002-04-11 Thread CHRIS FARMER

Marie, there is a thread going on this Oracle list about disk subsystem speed, I am 
going to forward a couple of the responses to you.  I think that it is reiterating 
that we need to have raid 0+1 in our PROD environment.

 [EMAIL PROTECTED] 04/10/02 01:06PM 


James Howerton wrote:
 
 John,
 
 We have the Hitachi 5800 series with RAID 5. The sales guys also said
 their system is
 s fast we need not worry about such minor details. Don't believe
 them!!! Write speed is SLOW. After we added bare drives for redo log
 files, archive logs,  conrtol files it made a dramatic difference in DB
 performance. Hitachi  some Sa's don't want to set up RAID 1+0 because
 it makes more work for them than a RAID 5 install.

Within the last month our development box was switched from RAID-1 to
RAID-5 because additional disk capacity was required. The big data
load job almost doubled in time from 150 minutes to 270 minutes due
to the double writes incurred by RAID-5 overhead.
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Re: disk subsystem performance question

2002-04-11 Thread Igor Neyman

Battery backup on the controller should help in this case.
If there is none, write back mode should be used (instead of write
through), loosing advantages of on-board caching (still helps with the
reads).

Igor Neyman, OCP DBA
[EMAIL PROTECTED]



- Original Message -
To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED]
Sent: Wednesday, April 10, 2002 6:58 PM


 Much of the supposed 'speed' may come from onboard
 caching on the controller.  There is the minor risk
 that a crash could come after Oracle commits the data
 and before it is actually written to disk.

 --- [EMAIL PROTECTED] wrote:
  Hi all,
 
  We are running both a Hitachi 7700E and a 9960 disk
  subsystem here and we
  are getting ready to move our production DBs from
  the old(7700E) to the
  new(9960) Hitachi.  We have had trouble in the
  past on the 7700E due to
  disk contention and layout, i.e. we weren't striped
  across the array groups
  very well this caused pretty poor I/O
  performance.This has been
  a learning experience for the DBAs and the SAs here
  for the logical vs.
  physical aspects of our disks.  Anyway, to make
  a long story short, we
  are ordering disk for the move to the 9960 and we
  have 2 choices in disk
  sizes - 18GB and 73GB, and 2 choices in RAID - 1+0
  and 5. I would like
  to get the smaller, faster 18GB drives in a RAID 1+0
  configuration and
  stripe our data across the array groups as wide as
  possible. However, I
  am running into objections from the Hitachi people
  that their system is
  s fast we need not worry about such minor
  details.   I'm having a
  hard time believing that given our I/O problems on
  the 7700E.  Performance
  is given a high priority here.
 
  What I would like to know is others' experience with
  disk subsystems -
  specifically Hitachi but EMC and others as well
   have you been able to
  throw the disk in and forget it or have you had
  success in getting to the
  dirty details?  Have you tested or noticed an
  improvement with smaller,
  faster drives in a disk subsystem like the Hitachi
  or have you traveled
  that path and found no noticeable improvement?
  I'm looking for either
  a) ammunition that my view is correct, or b) I'm
  wrong and we can get
  bigger drives which will make Enterprise Planning
  very happy from a $$$
  standpoint because our Hitachi capacity will last
  longer.
 
  We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft
  Financials version 8.
  2 production databases , one 400 GB and the other
  about 1TB. We've got
  some other production DBs but these are our big
  guys.
 
  Thanks in advance for any and all input - any help
  is greatly appreciated.
  I'd be happy to share any info we have found up to
  this point and our
  experiences on the 7700E as well if anyone is
  interested - despite the fact
  I will probably bore you to death   :-)
 
  John Dailey
  Oracle DBA
  ING Americas - Application Services
  Atlanta, GA
 
 
 
  --
  Please see the official ORACLE-L FAQ:
  http://www.orafaq.com
  --
  Author:
INET: [EMAIL PROTECTED]
 
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  ORACLE-L
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 =
 Pete Barnett
 Lead Database Administrator
 The Regence Group
 [EMAIL PROTECTED]

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Re: disk subsystem performance question

2002-04-11 Thread Gaja Krishna Vaidyanatha
To:
 Multiple recipients of list ORACLE-L
 [EMAIL PROTECTED]
  granaman@coxcc:
  .netSubject: 
Re: disk subsystem performance question
  Sent by:
  root@fatcity.
  com
  
  
  04/10/2002
  01:08 PM
  Please
  respond to
  ORACLE-L
  
  
  
  Short answer - NO!  Nobody's disk subsystem is so
 fast that no intelligence
  is required in the layout.  This is common vendor
 blather and one of the
  most popular myths.  I have been hearing it for at
 least six years - and it
  still isn't true.  Layout still makes a huge
 difference.  RAID levels still
  make a huge difference.  Cache won't solve all
 your problems (it does help
  though).  I've redone the disk layout on some of
 the biggest, fastest
  fully-loaded with cache EMC Syms available that
 had some don't worry about
  it layout and seen database throughput go up by
 as much as 8x.
  
  See Gaja's whitepaper on RAID at
 http://www.quest.com/whitepapers/Raid1.pdf
  .
  
  Don Granaman
  [certifiable oraSaurus]
  
  - Original Message -
  To: Multiple recipients of list ORACLE-L
 [EMAIL PROTECTED]
  Sent: Wednesday, April 10, 2002 10:38 AM
  
   Hi all,
  
   We are running both a Hitachi 7700E and a 9960
 disk subsystem here and we
   are getting ready to move our production DBs
 from the old(7700E) to the
   new(9960) Hitachi.  We have had trouble in
 the past on the 7700E due
  to
   disk contention and layout, i.e. we weren't
 striped across the array
  groups
   very well this caused pretty poor I/O
 performance.This has
  been
   a learning experience for the DBAs and the SAs
 here for the logical vs.
   physical aspects of our disks.  Anyway, to
 make a long story short,
  we
   are ordering disk for the move to the 9960 and
 we have 2 choices in disk
   sizes - 18GB and 73GB, and 2 choices in RAID -
 1+0 and 5. I would
  like
   to get the smaller, faster 18GB drives in a RAID
 1+0 configuration and
   stripe our data across the array groups as wide
 as possible. However,
  I
   am running into objections from the Hitachi
 people that their system is
   s fast we need not worry about such minor
 details.   I'm having a
   hard time believing that given our I/O problems
 on the 7700E.
  Performance
   is given a high priority here.
  
   What I would like to know is others' experience
 with disk subsystems -
   specifically Hitachi but EMC and others as
 well   have you been able
  to
   throw the disk in and forget it or have you
 had success in getting to
  the
   dirty details?  Have you tested or noticed
 an improvement with
  smaller,
   faster drives in a disk subsystem like the
 Hitachi or have you traveled
   that path and found no noticeable improvement?  
I'm looking for
  either
   a) ammunition that my view is correct, or b) I'm
 wrong and we can get
   bigger drives which will make Enterprise
 Planning very happy from a $$$
   standpoint because our Hitachi capacity will
 last longer.
  
   We are running Oracle 8.1.7 / AIX 4.3.3 /
 Peoplesoft Financials version
  8.
   2 production databases , one 400 GB and the
 other about 1TB. We've
  got
   some other production DBs but these are our big
 guys.
  
   Thanks in advance for any and all input - any
 help is greatly
  appreciated.
   I'd be happy to share any info we have found up
 to this point and our
   experiences on the 7700E as well if anyone is
 interested - despite the
  fact
   I will probably bore you to death   :-)
  
   John Dailey
   Oracle DBA
   ING Americas - Application Services
   Atlanta, GA
  
  
  
 
=== message truncated ===


=
Gaja Krishna Vaidyanatha
Director, Storage Management Products,
Quest Software, Inc.
Co-author - Oracle Performance Tuning 101
http://www.osborne.com/database_erp/0072131454/0072131454.shtml

__
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Yahoo! Tax Center - online filing with TurboTax
http://taxes.yahoo.com/
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-- 
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disk subsystem performance question

2002-04-10 Thread John . Dailey

Hi all,

We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
are getting ready to move our production DBs from the old(7700E) to the
new(9960) Hitachi.  We have had trouble in the past on the 7700E due to
disk contention and layout, i.e. we weren't striped across the array groups
very well this caused pretty poor I/O performance.This has been
a learning experience for the DBAs and the SAs here for the logical vs.
physical aspects of our disks.  Anyway, to make a long story short, we
are ordering disk for the move to the 9960 and we have 2 choices in disk
sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would like
to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
stripe our data across the array groups as wide as possible. However, I
am running into objections from the Hitachi people that their system is
s fast we need not worry about such minor details.   I'm having a
hard time believing that given our I/O problems on the 7700E.  Performance
is given a high priority here.

What I would like to know is others' experience with disk subsystems -
specifically Hitachi but EMC and others as well   have you been able to
throw the disk in and forget it or have you had success in getting to the
dirty details?  Have you tested or noticed an improvement with smaller,
faster drives in a disk subsystem like the Hitachi or have you traveled
that path and found no noticeable improvement?  I'm looking for either
a) ammunition that my view is correct, or b) I'm wrong and we can get
bigger drives which will make Enterprise Planning very happy from a $$$
standpoint because our Hitachi capacity will last longer.

We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft Financials version 8.
2 production databases , one 400 GB and the other about 1TB. We've got
some other production DBs but these are our big guys.

Thanks in advance for any and all input - any help is greatly appreciated.
I'd be happy to share any info we have found up to this point and our
experiences on the 7700E as well if anyone is interested - despite the fact
I will probably bore you to death   :-)

John Dailey
Oracle DBA
ING Americas - Application Services
Atlanta, GA



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-- 
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  INET: [EMAIL PROTECTED]

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RE: disk subsystem performance question

2002-04-10 Thread DENNIS WILLIAMS

John - I haven't experienced the Hitachi disks. To me the key question is
how much battery-backed cache the subsystem has. I believe there tends to be
a gap in knowledge between DBAs and the disk people. The two don't always
understand each other or speak the same language. The Oracle books tend to
assume stand-alone disks and issues like raw partitions. The disk people
keep coming with new innovations. Some of those innovations may help
database performance and some may hurt. I'm still waiting for the definitive
book or at least a white paper so I can understand the issues.
Dennis Williams
DBA
Lifetouch, Inc.
[EMAIL PROTECTED]


-Original Message-
Sent: Wednesday, April 10, 2002 10:38 AM
To: Multiple recipients of list ORACLE-L


Hi all,

We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
are getting ready to move our production DBs from the old(7700E) to the
new(9960) Hitachi.  We have had trouble in the past on the 7700E due to
disk contention and layout, i.e. we weren't striped across the array groups
very well this caused pretty poor I/O performance.This has been
a learning experience for the DBAs and the SAs here for the logical vs.
physical aspects of our disks.  Anyway, to make a long story short, we
are ordering disk for the move to the 9960 and we have 2 choices in disk
sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would like
to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
stripe our data across the array groups as wide as possible. However, I
am running into objections from the Hitachi people that their system is
s fast we need not worry about such minor details.   I'm having a
hard time believing that given our I/O problems on the 7700E.  Performance
is given a high priority here.

What I would like to know is others' experience with disk subsystems -
specifically Hitachi but EMC and others as well   have you been able to
throw the disk in and forget it or have you had success in getting to the
dirty details?  Have you tested or noticed an improvement with smaller,
faster drives in a disk subsystem like the Hitachi or have you traveled
that path and found no noticeable improvement?  I'm looking for either
a) ammunition that my view is correct, or b) I'm wrong and we can get
bigger drives which will make Enterprise Planning very happy from a $$$
standpoint because our Hitachi capacity will last longer.

We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft Financials version 8.
2 production databases , one 400 GB and the other about 1TB. We've got
some other production DBs but these are our big guys.

Thanks in advance for any and all input - any help is greatly appreciated.
I'd be happy to share any info we have found up to this point and our
experiences on the 7700E as well if anyone is interested - despite the fact
I will probably bore you to death   :-)

John Dailey
Oracle DBA
ING Americas - Application Services
Atlanta, GA



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  INET: [EMAIL PROTECTED]

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Re: disk subsystem performance question

2002-04-10 Thread James Howerton

John,

We have the Hitachi 5800 series with RAID 5. The sales guys also said
their system is
s fast we need not worry about such minor details. Don't believe
them!!! Write speed is SLOW. After we added bare drives for redo log
files, archive logs,  conrtol files it made a dramatic difference in DB
performance. Hitachi  some Sa's don't want to set up RAID 1+0 because
it makes more work for them than a RAID 5 install.

HTH
...JIM... 

 [EMAIL PROTECTED] 4/10/02 10:38:26 AM 
Hi all,

We are running both a Hitachi 7700E and a 9960 disk subsystem here and
we
are getting ready to move our production DBs from the old(7700E) to
the
new(9960) Hitachi.  We have had trouble in the past on the 7700E
due to
disk contention and layout, i.e. we weren't striped across the array
groups
very well this caused pretty poor I/O performance.This has
been
a learning experience for the DBAs and the SAs here for the logical
vs.
physical aspects of our disks.  Anyway, to make a long story short,
we
are ordering disk for the move to the 9960 and we have 2 choices in
disk
sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would
like
to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
stripe our data across the array groups as wide as possible.
However, I
am running into objections from the Hitachi people that their system
is
s fast we need not worry about such minor details.   I'm having
a
hard time believing that given our I/O problems on the 7700E. 
Performance
is given a high priority here.

What I would like to know is others' experience with disk subsystems -
specifically Hitachi but EMC and others as well   have you been
able to
throw the disk in and forget it or have you had success in getting to
the
dirty details?  Have you tested or noticed an improvement with
smaller,
faster drives in a disk subsystem like the Hitachi or have you
traveled
that path and found no noticeable improvement?  I'm looking for
either
a) ammunition that my view is correct, or b) I'm wrong and we can get
bigger drives which will make Enterprise Planning very happy from a
$$$
standpoint because our Hitachi capacity will last longer.

We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft Financials version
8.
2 production databases , one 400 GB and the other about 1TB. We've
got
some other production DBs but these are our big guys.

Thanks in advance for any and all input - any help is greatly
appreciated.
I'd be happy to share any info we have found up to this point and our
experiences on the 7700E as well if anyone is interested - despite the
fact
I will probably bore you to death   :-)

John Dailey
Oracle DBA
ING Americas - Application Services
Atlanta, GA



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(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).



Re: disk subsystem performance question

2002-04-10 Thread Don Granaman

Short answer - NO!  Nobody's disk subsystem is so fast that no intelligence
is required in the layout.  This is common vendor blather and one of the
most popular myths.  I have been hearing it for at least six years - and it
still isn't true.  Layout still makes a huge difference.  RAID levels still
make a huge difference.  Cache won't solve all your problems (it does help
though).  I've redone the disk layout on some of the biggest, fastest
fully-loaded with cache EMC Syms available that had some don't worry about
it layout and seen database throughput go up by as much as 8x.

See Gaja's whitepaper on RAID at http://www.quest.com/whitepapers/Raid1.pdf
.

Don Granaman
[certifiable oraSaurus]

- Original Message -
To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED]
Sent: Wednesday, April 10, 2002 10:38 AM


 Hi all,

 We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
 are getting ready to move our production DBs from the old(7700E) to the
 new(9960) Hitachi.  We have had trouble in the past on the 7700E due
to
 disk contention and layout, i.e. we weren't striped across the array
groups
 very well this caused pretty poor I/O performance.This has
been
 a learning experience for the DBAs and the SAs here for the logical vs.
 physical aspects of our disks.  Anyway, to make a long story short, we
 are ordering disk for the move to the 9960 and we have 2 choices in disk
 sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would like
 to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
 stripe our data across the array groups as wide as possible. However,
I
 am running into objections from the Hitachi people that their system is
 s fast we need not worry about such minor details.   I'm having a
 hard time believing that given our I/O problems on the 7700E.  Performance
 is given a high priority here.

 What I would like to know is others' experience with disk subsystems -
 specifically Hitachi but EMC and others as well   have you been able
to
 throw the disk in and forget it or have you had success in getting to
the
 dirty details?  Have you tested or noticed an improvement with
smaller,
 faster drives in a disk subsystem like the Hitachi or have you traveled
 that path and found no noticeable improvement?  I'm looking for either
 a) ammunition that my view is correct, or b) I'm wrong and we can get
 bigger drives which will make Enterprise Planning very happy from a $$$
 standpoint because our Hitachi capacity will last longer.

 We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft Financials version 8.
 2 production databases , one 400 GB and the other about 1TB. We've got
 some other production DBs but these are our big guys.

 Thanks in advance for any and all input - any help is greatly appreciated.
 I'd be happy to share any info we have found up to this point and our
 experiences on the 7700E as well if anyone is interested - despite the
fact
 I will probably bore you to death   :-)

 John Dailey
 Oracle DBA
 ING Americas - Application Services
 Atlanta, GA



 --
 Please see the official ORACLE-L FAQ: http://www.orafaq.com
 --
 Author:
   INET: [EMAIL PROTECTED]

 Fat City Network Services-- (858) 538-5051  FAX: (858) 538-5051
 San Diego, California-- Public Internet access / Mailing Lists
 
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 to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
 the message BODY, include a line containing: UNSUB ORACLE-L
 (or the name of mailing list you want to be removed from).  You may
 also send the HELP command for other information (like subscribing).

-- 
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-- 
Author: Don Granaman
  INET: [EMAIL PROTECTED]

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(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).



Re: disk subsystem performance question

2002-04-10 Thread Charlie Mengler



James Howerton wrote:
 
 John,
 
 We have the Hitachi 5800 series with RAID 5. The sales guys also said
 their system is
 s fast we need not worry about such minor details. Don't believe
 them!!! Write speed is SLOW. After we added bare drives for redo log
 files, archive logs,  conrtol files it made a dramatic difference in DB
 performance. Hitachi  some Sa's don't want to set up RAID 1+0 because
 it makes more work for them than a RAID 5 install.

Within the last month our development box was switched from RAID-1 to
RAID-5 because additional disk capacity was required. The big data
load job almost doubled in time from 150 minutes to 270 minutes due
to the double writes incurred by RAID-5 overhead.
-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Charlie Mengler
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also send the HELP command for other information (like subscribing).



RE: disk subsystem performance question

2002-04-10 Thread Deshpande, Kirti

John,
 We use 7700E. Most all EMC is going out and being replaced by HDS RAID-5.
(What it costs is more important that what it does). Everything we have is
on RAID-5 these days.
 HDS Techies and our Capacity Planners (who do the disk assignments to
Servers) told me the following: The 18GB drives are arranged by 'parity
groups' inside the array and are striped at H/W level. Each such group is
then chopped off as 7-8GB disk device for the target server (/dev/hdiskXX).
Disk devices on the server with the same 'parity group' can be considered as
one hard disk. Sys Admins then build the VGs of such hdisks with identical
parity group. We then ask them to build LVs for FSs to be used for data and
index separation. This scheme has been working well for us for the time
being. I am still hoping to someday go back to RAID 1+0. Pl check with your
HDS Techies about this 'parity group' theory and see what they are doing for
you. Please update us if this theory (as was told to us) works or it was
just to pacify us. 
 The NV Cache gets immediately saturated. The db size and demand for data
will always be way larger than the available cache (and cash;)

 Good Luck..

- Kirti 

-Original Message-
Sent: Wednesday, April 10, 2002 12:09 PM
To: Multiple recipients of list ORACLE-L


Short answer - NO!  Nobody's disk subsystem is so fast that no intelligence
is required in the layout.  This is common vendor blather and one of the
most popular myths.  I have been hearing it for at least six years - and it
still isn't true.  Layout still makes a huge difference.  RAID levels still
make a huge difference.  Cache won't solve all your problems (it does help
though).  I've redone the disk layout on some of the biggest, fastest
fully-loaded with cache EMC Syms available that had some don't worry about
it layout and seen database throughput go up by as much as 8x.

See Gaja's whitepaper on RAID at http://www.quest.com/whitepapers/Raid1.pdf
.

Don Granaman
[certifiable oraSaurus]

- Original Message -
To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED]
Sent: Wednesday, April 10, 2002 10:38 AM


 Hi all,

 We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
 are getting ready to move our production DBs from the old(7700E) to the
 new(9960) Hitachi.  We have had trouble in the past on the 7700E due
to
 disk contention and layout, i.e. we weren't striped across the array
groups
 very well this caused pretty poor I/O performance.This has
been
 a learning experience for the DBAs and the SAs here for the logical vs.
 physical aspects of our disks.  Anyway, to make a long story short, we
 are ordering disk for the move to the 9960 and we have 2 choices in disk
 sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would like
 to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
 stripe our data across the array groups as wide as possible. However,
I
 am running into objections from the Hitachi people that their system is
 s fast we need not worry about such minor details.   I'm having a
 hard time believing that given our I/O problems on the 7700E.  Performance
 is given a high priority here.

 What I would like to know is others' experience with disk subsystems -
 specifically Hitachi but EMC and others as well   have you been able
to
 throw the disk in and forget it or have you had success in getting to
the
 dirty details?  Have you tested or noticed an improvement with
smaller,
 faster drives in a disk subsystem like the Hitachi or have you traveled
 that path and found no noticeable improvement?  I'm looking for either
 a) ammunition that my view is correct, or b) I'm wrong and we can get
 bigger drives which will make Enterprise Planning very happy from a $$$
 standpoint because our Hitachi capacity will last longer.

 We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft Financials version 8.
 2 production databases , one 400 GB and the other about 1TB. We've got
 some other production DBs but these are our big guys.

 Thanks in advance for any and all input - any help is greatly appreciated.
 I'd be happy to share any info we have found up to this point and our
 experiences on the 7700E as well if anyone is interested - despite the
fact
 I will probably bore you to death   :-)

 John Dailey
 Oracle DBA
 ING Americas - Application Services
 Atlanta, GA



-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Deshpande, Kirti
  INET: [EMAIL PROTECTED]

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San Diego, California-- Public Internet access / Mailing Lists

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to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  

Re: disk subsystem performance question

2002-04-10 Thread Peter Barnett

Much of the supposed 'speed' may come from onboard
caching on the controller.  There is the minor risk
that a crash could come after Oracle commits the data
and before it is actually written to disk.

--- [EMAIL PROTECTED] wrote:
 Hi all,
 
 We are running both a Hitachi 7700E and a 9960 disk
 subsystem here and we
 are getting ready to move our production DBs from
 the old(7700E) to the
 new(9960) Hitachi.  We have had trouble in the
 past on the 7700E due to
 disk contention and layout, i.e. we weren't striped
 across the array groups
 very well this caused pretty poor I/O
 performance.This has been
 a learning experience for the DBAs and the SAs here
 for the logical vs.
 physical aspects of our disks.  Anyway, to make
 a long story short, we
 are ordering disk for the move to the 9960 and we
 have 2 choices in disk
 sizes - 18GB and 73GB, and 2 choices in RAID - 1+0
 and 5. I would like
 to get the smaller, faster 18GB drives in a RAID 1+0
 configuration and
 stripe our data across the array groups as wide as
 possible. However, I
 am running into objections from the Hitachi people
 that their system is
 s fast we need not worry about such minor
 details.   I'm having a
 hard time believing that given our I/O problems on
 the 7700E.  Performance
 is given a high priority here.
 
 What I would like to know is others' experience with
 disk subsystems -
 specifically Hitachi but EMC and others as well 
  have you been able to
 throw the disk in and forget it or have you had
 success in getting to the
 dirty details?  Have you tested or noticed an
 improvement with smaller,
 faster drives in a disk subsystem like the Hitachi
 or have you traveled
 that path and found no noticeable improvement? 
 I'm looking for either
 a) ammunition that my view is correct, or b) I'm
 wrong and we can get
 bigger drives which will make Enterprise Planning
 very happy from a $$$
 standpoint because our Hitachi capacity will last
 longer.
 
 We are running Oracle 8.1.7 / AIX 4.3.3 / Peoplesoft
 Financials version 8.
 2 production databases , one 400 GB and the other
 about 1TB. We've got
 some other production DBs but these are our big
 guys.
 
 Thanks in advance for any and all input - any help
 is greatly appreciated.
 I'd be happy to share any info we have found up to
 this point and our
 experiences on the 7700E as well if anyone is
 interested - despite the fact
 I will probably bore you to death   :-)
 
 John Dailey
 Oracle DBA
 ING Americas - Application Services
 Atlanta, GA
 
 
 
 -- 
 Please see the official ORACLE-L FAQ:
 http://www.orafaq.com
 -- 
 Author: 
   INET: [EMAIL PROTECTED]
 
 Fat City Network Services-- (858) 538-5051  FAX:
 (858) 538-5051
 San Diego, California-- Public Internet
 access / Mailing Lists


 To REMOVE yourself from this mailing list, send an
 E-Mail message
 to: [EMAIL PROTECTED] (note EXACT spelling of
 'ListGuru') and in
 the message BODY, include a line containing: UNSUB
 ORACLE-L
 (or the name of mailing list you want to be removed
 from).  You may
 also send the HELP command for other information
 (like subscribing).


=
Pete Barnett
Lead Database Administrator
The Regence Group
[EMAIL PROTECTED]

__
Do You Yahoo!?
Yahoo! Tax Center - online filing with TurboTax
http://taxes.yahoo.com/
-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Peter Barnett
  INET: [EMAIL PROTECTED]

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San Diego, California-- Public Internet access / Mailing Lists

To REMOVE yourself from this mailing list, send an E-Mail message
to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).



Re: disk subsystem performance question

2002-04-10 Thread John . Dailey


Thanks for all the replies.  We are determined to lay out the data as
well as we can across the disks we are about to purchase - with the goal of
striping across array groups and smaller, faster drives. The real
argument for us is 18GB vs. 73GB disk drives and how we can stripe. The
Hitachi is configured into groups of 4 physical disks called parity
groups and you can choose RAID 5 or RAID 1+0 for that 4 disk set.If
you have 73GB drives in a 4-disk RAID 5 configuration you get roughly 219GB
of usable space in each parity group (this is what we are being told is the
best option for us).This means our heavily concurrently accessed 400GB
production database goes on 2 parity groups (2 sets of 4 disks).  To
me, this sounds like a nightmare waiting to happen and we are trying to
stop it.The 18GB drives are less capacity but we can get ourselves
spread over more parity groups for better concurrency. We do have about
10GB of cache but it is being shared across the enterprise with various
other applications.  We as a DBA group are really trying to sell the
18GB RAID 1+0 drive solution especially after reading the groups'
experiences - unfortunately we are fighting a lot of marketing hype.

If anyone has additional experiences or feedback with Hitachi or EMC they
would like to share or comments (agree/disagree) with my thoughts, I'd love
to hear them.   I'm open for learning!

Thanks,

John Dailey
Oracle DBA
ING Americas - Application Services
Atlanta, GA




   

Don   

GranamanTo: Multiple recipients of list ORACLE-L 
[EMAIL PROTECTED]   
granaman@coxcc:   

.netSubject: Re: disk subsystem performance 
question  
Sent by:   

root@fatcity.  

com

   

   

04/10/2002 

01:08 PM   

Please 

respond to 

ORACLE-L   

   

   





Short answer - NO!  Nobody's disk subsystem is so fast that no intelligence
is required in the layout.  This is common vendor blather and one of the
most popular myths.  I have been hearing it for at least six years - and it
still isn't true.  Layout still makes a huge difference.  RAID levels still
make a huge difference.  Cache won't solve all your problems (it does help
though).  I've redone the disk layout on some of the biggest, fastest
fully-loaded with cache EMC Syms available that had some don't worry about
it layout and seen database throughput go up by as much as 8x.

See Gaja's whitepaper on RAID at http://www.quest.com/whitepapers/Raid1.pdf
.

Don Granaman
[certifiable oraSaurus]

- Original Message -
To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED]
Sent: Wednesday, April 10, 2002 10:38 AM


 Hi all,

 We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
 are getting ready to move our production DBs from the old(7700E) to the
 new(9960) Hitachi.  We have had trouble in the past on the 7700E due
to
 disk contention and layout, i.e. we weren't striped across the array
groups
 very well this caused pretty poor I/O performance.This has
been
 a learning experience for the DBAs and the SAs here for the logical vs.
 physical aspects of our disks.  Anyway, to make a long story short,
we
 are ordering disk for the move to the 9960 and we have 2 choices in disk
 sizes - 18GB and 73GB, and 2 choices in RAID - 1+0

Re: disk subsystem performance question

2002-04-10 Thread Charlie Mengler

I believe RAID-1+0 has more cost than benefit.
I want to see  measure total I/O's to each spindle.
While RAID-1 has higher cost to maintain, it gives
me maximum flexibility to evenly distribute I/O loads.
I contend that with proper table partitioning I can
achieve  sustain higher I/O rates with RAID-1 than
can be gotten from RAID-1+0.

HTH  YMMV

HAND!

[EMAIL PROTECTED] wrote:
 
 Thanks for all the replies.  We are determined to lay out the data as
 well as we can across the disks we are about to purchase - with the goal of
 striping across array groups and smaller, faster drives. The real
 argument for us is 18GB vs. 73GB disk drives and how we can stripe. The
 Hitachi is configured into groups of 4 physical disks called parity
 groups and you can choose RAID 5 or RAID 1+0 for that 4 disk set.If
 you have 73GB drives in a 4-disk RAID 5 configuration you get roughly 219GB
 of usable space in each parity group (this is what we are being told is the
 best option for us).This means our heavily concurrently accessed 400GB
 production database goes on 2 parity groups (2 sets of 4 disks).  To
 me, this sounds like a nightmare waiting to happen and we are trying to
 stop it.The 18GB drives are less capacity but we can get ourselves
 spread over more parity groups for better concurrency. We do have about
 10GB of cache but it is being shared across the enterprise with various
 other applications.  We as a DBA group are really trying to sell the
 18GB RAID 1+0 drive solution especially after reading the groups'
 experiences - unfortunately we are fighting a lot of marketing hype.
 
 If anyone has additional experiences or feedback with Hitachi or EMC they
 would like to share or comments (agree/disagree) with my thoughts, I'd love
 to hear them.   I'm open for learning!
 
 Thanks,
 
 John Dailey
 Oracle DBA
 ING Americas - Application Services
 Atlanta, GA
 
 
 Don
 GranamanTo: Multiple recipients of list 
ORACLE-L [EMAIL PROTECTED]
 granaman@coxcc:
 .netSubject: Re: disk subsystem performance 
question
 Sent by:
 root@fatcity.
 com
 
 
 04/10/2002
 01:08 PM
 Please
 respond to
 ORACLE-L
 
 
 
 Short answer - NO!  Nobody's disk subsystem is so fast that no intelligence
 is required in the layout.  This is common vendor blather and one of the
 most popular myths.  I have been hearing it for at least six years - and it
 still isn't true.  Layout still makes a huge difference.  RAID levels still
 make a huge difference.  Cache won't solve all your problems (it does help
 though).  I've redone the disk layout on some of the biggest, fastest
 fully-loaded with cache EMC Syms available that had some don't worry about
 it layout and seen database throughput go up by as much as 8x.
 
 See Gaja's whitepaper on RAID at http://www.quest.com/whitepapers/Raid1.pdf
 .
 
 Don Granaman
 [certifiable oraSaurus]
 
 - Original Message -
 To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED]
 Sent: Wednesday, April 10, 2002 10:38 AM
 
  Hi all,
 
  We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
  are getting ready to move our production DBs from the old(7700E) to the
  new(9960) Hitachi.  We have had trouble in the past on the 7700E due
 to
  disk contention and layout, i.e. we weren't striped across the array
 groups
  very well this caused pretty poor I/O performance.This has
 been
  a learning experience for the DBAs and the SAs here for the logical vs.
  physical aspects of our disks.  Anyway, to make a long story short,
 we
  are ordering disk for the move to the 9960 and we have 2 choices in disk
  sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would
 like
  to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
  stripe our data across the array groups as wide as possible. However,
 I
  am running into objections from the Hitachi people that their system is
  s fast we need not worry about such minor details.   I'm having a
  hard time believing that given our I/O problems on the 7700E.
 Performance
  is given a high priority here.
 
  What I would like to know is others' experience with disk subsystems -
  specifically Hitachi but EMC and others as well   have you been able
 to
  throw the disk in and forget it or have you had success in getting to
 the
  dirty details?  Have you tested or noticed an improvement with
 smaller,
  faster drives in a disk subsystem like the Hitachi or have you traveled
  that path and found no noticeable improvement?  I'm looking for
 either
  a) ammunition that my view is correct, or b) I'm wrong and we can get
  bigger drives which will make Enterprise Planning

RE: disk subsystem performance question

2002-04-10 Thread Deshpande, Kirti

John,
 I agree with the 18GB drives implementation and pushing for more 'parity
groups'. That's what we did. Now, HDS was back to sell more disk and backup
soultions to us. I am not sure what we have agreed to purchase. A cache of
10GB for the 400GB database is nothing. I bet you will have tables larger
than the cache size. A single FTS on these tables will flush the whole
cache... We have 16GB cache (I think I remember that right, and is the max
for 7700E), and that is not enough for several servers that the cabinet
supports. 

- Kirti 

-Original Message-
Sent: Wednesday, April 10, 2002 7:08 PM
To: Multiple recipients of list ORACLE-L



Thanks for all the replies.  We are determined to lay out the data as
well as we can across the disks we are about to purchase - with the goal of
striping across array groups and smaller, faster drives. The real
argument for us is 18GB vs. 73GB disk drives and how we can stripe. The
Hitachi is configured into groups of 4 physical disks called parity
groups and you can choose RAID 5 or RAID 1+0 for that 4 disk set.If
you have 73GB drives in a 4-disk RAID 5 configuration you get roughly 219GB
of usable space in each parity group (this is what we are being told is the
best option for us).This means our heavily concurrently accessed 400GB
production database goes on 2 parity groups (2 sets of 4 disks).  To
me, this sounds like a nightmare waiting to happen and we are trying to
stop it.The 18GB drives are less capacity but we can get ourselves
spread over more parity groups for better concurrency. We do have about
10GB of cache but it is being shared across the enterprise with various
other applications.  We as a DBA group are really trying to sell the
18GB RAID 1+0 drive solution especially after reading the groups'
experiences - unfortunately we are fighting a lot of marketing hype.

If anyone has additional experiences or feedback with Hitachi or EMC they
would like to share or comments (agree/disagree) with my thoughts, I'd love
to hear them.   I'm open for learning!

Thanks,

John Dailey
Oracle DBA
ING Americas - Application Services
Atlanta, GA




 

Don

GranamanTo: Multiple recipients of list
ORACLE-L [EMAIL PROTECTED]   
granaman@coxcc:

.netSubject: Re: disk subsystem
performance question  
Sent by:

root@fatcity.

com

 

 

04/10/2002

01:08 PM

Please

respond to

ORACLE-L

 

 





Short answer - NO!  Nobody's disk subsystem is so fast that no intelligence
is required in the layout.  This is common vendor blather and one of the
most popular myths.  I have been hearing it for at least six years - and it
still isn't true.  Layout still makes a huge difference.  RAID levels still
make a huge difference.  Cache won't solve all your problems (it does help
though).  I've redone the disk layout on some of the biggest, fastest
fully-loaded with cache EMC Syms available that had some don't worry about
it layout and seen database throughput go up by as much as 8x.

See Gaja's whitepaper on RAID at http://www.quest.com/whitepapers/Raid1.pdf
.

Don Granaman
[certifiable oraSaurus]

- Original Message -
To: Multiple recipients of list ORACLE-L [EMAIL PROTECTED]
Sent: Wednesday, April 10, 2002 10:38 AM


 Hi all,

 We are running both a Hitachi 7700E and a 9960 disk subsystem here and we
 are getting ready to move our production DBs from the old(7700E) to the
 new(9960) Hitachi.  We have had trouble in the past on the 7700E due
to
 disk contention and layout, i.e. we weren't striped across the array
groups
 very well this caused pretty poor I/O performance.This has
been
 a learning experience for the DBAs and the SAs here for the logical vs.
 physical aspects of our disks.  Anyway, to make a long story short,
we
 are ordering disk for the move to the 9960 and we have 2 choices in disk
 sizes - 18GB and 73GB, and 2 choices in RAID - 1+0 and 5. I would
like
 to get the smaller, faster 18GB drives in a RAID 1+0 configuration and
 stripe our data across the array groups as wide as possible. However,
I
 am running into objections from the Hitachi people that their system is
 s fast we need not worry about such minor details.   I'm having a
 hard time believing that given our I/O problems on the 7700E.
Performance
 is given a high priority here.

 What I would like to know is others' experience with disk subsystems -
 specifically Hitachi but EMC and others as well   have you been able
to
 throw the disk in and forget it or have you had success in getting to
the
 dirty details?  Have you tested or noticed an improvement with
smaller,
 faster drives in a disk subsystem like