| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
 |
 | |||
| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
|
| |||
Home -> Community -> Mailing Lists -> Oracle-L -> RE: I/O Performance/bottlenecks on EMC Symmetrix
We saw
this at a previous location and we found that we had logical volumes on the same
disk.. Used for different applications, and even different systems!! For
example-someone placed TEMP for DB1 and TEMP for DB2 on the same disk
unknowingly.... This created just a small contention
problem...
This
is a common problem when large sym cabinets are set up with "logical volumes
split to different systems".<FONT
face=Arial color=#0000ff size=2>
Each
LV may be defined such that you wont know that they are on the same disk.
If you are using BCV's, and clustering-it get's even more detailed and
confusing...
<FONT face=Arial color=#0000ff
size=2>
Have
the EMC rep come in, take a look at the "bin" file of your sym cabinet(s).. And
see where the logical volumes are living.. Draw a map of the bin file with
a graphical representation of each LV, and where they
live...
<FONT face=Arial color=#0000ff
size=2>
<FONT face=Arial color=#0000ff
size=2>Greg
<FONT face=Tahoma
size=2>-----Original Message-----From: Hallas John
[mailto:John.Hallas_at_btcellnet.net]Sent: Thursday, September 13,
2001 10:01 AMTo: Multiple recipients of list
ORACLE-LSubject: RE: I/O Performance/bottlenecks on EMC
Symmetrix
At one site I worked using Oracle Financials we were having
serious performance problems at what seemed to us random intervals. Spent
months looking at the database after the Unix boys had said that there was no
way we could have I/O problems with the throughput capabililities of EMC and
the Symetrix set up we had.
Eventually turned out that 3 systems were sharing the same
disks and the disks had not been striped. Therefore other system were causing
us performance problems.
If you have an EMC support contract which I think you must
have you, the SA's get all the free GUI tools that allow them to look at
channels and logical/physical layout. Ask them about.
John
-----Original Message----- From:
nlzanen1_at_EY.NL [<A
href="mailto:nlzanen1_at_EY.NL">mailto:nlzanen1_at_EY.NL] <FONT
size=2>Sent: 13 September 01 12:55 To: Multiple
recipients of list ORACLE-L Subject: I/O
Performance/bottlenecks on EMC Symmetrix
!! Please do not post Off Topic to this List !!
Hi All,
Does anybody here on the list have experience with
EMC/symmetrix storage units.?
We have our databases on this machine and I have a feeling the
the I/O performance is not very good. I can not proof
it since I do not have any experience/data/access to
that machine. We do however have a very cooperative
UNIX group but they also lack experience with performance on <FONT
size=2>this machine.
Who can give me pointers about I/O throughput that can be
reached, configuration pittfalls etc..
Example: RS6000 8CPU's and 4Gb memory
with storage on EMC/symmetrix. Job takes about 2 hours
to complete.
F50 1 CPU 1Gb memory (TEST machine) local disks. same job
takes 0.5 hours to complete.
Jack
<FONT
size=2>=====================================================================De informatie verzonden in dit e-mailbericht is vertrouwelijk en is uitsluitend bestemd voor de geadresseerde. Openbaarmaking, vermenigvuldiging, verspreiding en/of verstrekking van deze informatie aan derden is, behoudens voorafgaande schriftelijke toestemming van Ernst & Young, niet toegestaan. Ernst & Young staat niet in voor de juiste en volledige overbrenging van de inhoud van een verzonden e-mailbericht, noch voor tijdige ontvangst daarvan. Ernst & Young kan niet garanderen dat een verzonden e-mailbericht vrij is van virussen, noch dat e-mailberichten worden overgebracht zonder inbreuk of tussenkomst van onbevoegde derden.
size=2>=====================================================================The information contained in this communication is confidential and is intended solely for the use of the individual or entity to whom it is addressed. You should not copy, disclose or distribute this communication <FONT size=2>without the authority of Ernst & Young. Ernst & Young is neither liable for the proper and complete transmission of the information contained in this <FONT size=2>communication nor for any delay in its receipt. Ernst & Young does not guarantee that the integrity of this communication has been maintained nor that the communication is free of viruses, interceptions or interference. If you are not the intended recipient of this communication please return the communication to the sender and delete and destroy all copies.
size=2>=====================================================================
 |
 |