Re: troubleshooting slow I/O performance.
From: Andrew Kerber <andrew.kerber_at_gmail.com>
Date: Mon, 7 May 2018 11:58:34 -0500
Message-Id: <C917B169-2ECA-4396-8455-3B0813DDF104_at_gmail.com>
>> On Mon, 7 May 2018, 21:00 Chris Stephens, <cstephens16_at_gmail.com> wrote:
>> We have a new 5 node 12.2 RAC system that is not performing the way we want.
>>
>> The glaring issue is that "db file sequential read"'s are taking ~10ms. before i lob this over to the storage administrators, are there any possible areas in the clusterware/database configuration that I should investigate first? i have root access to all of the nodes. is there any information i can collect that would expedite the process of figuring out why we have such slow I/O times?
>>
>> slow i/o was discovered by running slob. if you don't know about that tool, you should. we all owe kevin a debt of gratitude. ;)
>>
>> if nothing else, i hope to learn a little more about storage than i currently know (which isn't much).
>>
>> thanks for any help.
>>
>> chris
>>
Date: Mon, 7 May 2018 11:58:34 -0500
Message-Id: <C917B169-2ECA-4396-8455-3B0813DDF104_at_gmail.com>
physical or virtual?
Sent from my iPhone
> On May 7, 2018, at 11:54 AM, Stefan Knecht <knecht.stefan_at_gmail.com> wrote: > > Some details would help: > > - ASM or FS? Type of FS? > - LUNs? Numbers, sizes? > - metal? SSD? Type of path to the disks? > > Etc... > >
>> On Mon, 7 May 2018, 21:00 Chris Stephens, <cstephens16_at_gmail.com> wrote:
>> We have a new 5 node 12.2 RAC system that is not performing the way we want.
>>
>> The glaring issue is that "db file sequential read"'s are taking ~10ms. before i lob this over to the storage administrators, are there any possible areas in the clusterware/database configuration that I should investigate first? i have root access to all of the nodes. is there any information i can collect that would expedite the process of figuring out why we have such slow I/O times?
>>
>> slow i/o was discovered by running slob. if you don't know about that tool, you should. we all owe kevin a debt of gratitude. ;)
>>
>> if nothing else, i hope to learn a little more about storage than i currently know (which isn't much).
>>
>> thanks for any help.
>>
>> chris
>>
-- http://www.freelists.org/webpage/oracle-lReceived on Mon May 07 2018 - 18:58:34 CEST