Re: Transparent HugePages causing crashes?
From: Niall Litchfield <niall.litchfield_at_gmail.com>
Date: Mon, 10 Jun 2013 20:07:37 +0100
Message-ID: <CABe10sZeTtk9hPD-BvHipCkpV8U4b6qQTaE+3PXCrzcukbCc7Q_at_mail.gmail.com>
Likely depends on the source. The upgrade guide and best practices papers for 11.2 say to gather system statistics with a representative workload. The performance best practices paper says leave at default. There used to be (and probably still are) other similar examples. All that really means is that Oracle employs humans who produce work in line with their skills and experience and towards the company goals as understood by their management at the time. Given a sufficient timeframe I'm sure that other companies documents also exhibit similar behavior. (and then there's always the old riposte "when the facts change, I change my mind. What do you do?") . The sooner people understand that "best practice" or "recommendation" usually means "common behavior we've seen in reputable places" the better. Or they could read things like ITIL that specifically describe best practices as a moving target and not a goal. On Jun 10, 2013 7:37 PM, "Kevin Closson" <ora_kclosson_at_yahoo.com> wrote:
>
> That MOS note says "highly recommends the use of standard HugePages" but
> I've also seen documentation that says Oracle strongly recommends AMM. Uh,
> ok.
>
>
>
>
> ________________________________
> From: Rich Jesse <rjoralist2_at_society.servebeer.com>
> To: oracle-l_at_freelists.org
> Sent: Thursday, June 6, 2013 7:59 AM
> Subject: Transparent HugePages causing crashes?
>
>
> Hey all,
>
> MOS has a new alert 1557478.1 that says "Because Transparent HugePages are
> known to cause unexpected node reboots and performance problems with RAC,
> Oracle strongly advises to disable the use of Transparent HugePages."
>
> However, I can't find anything searching for issues with THP in all the
> usual places. Is this just a RAC issue? Specific to Oracle instances
> running on later Linux releases?
>
> THP seems more like AIX's 64k medium pages and I was hoping to use them to
> help prevent DBA errors in sizing traditional HugePages.
>
> Anyone using THP?
>
> Rich
>
> --
> http://www.freelists.org/webpage/oracle-l
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>
Date: Mon, 10 Jun 2013 20:07:37 +0100
Message-ID: <CABe10sZeTtk9hPD-BvHipCkpV8U4b6qQTaE+3PXCrzcukbCc7Q_at_mail.gmail.com>
Likely depends on the source. The upgrade guide and best practices papers for 11.2 say to gather system statistics with a representative workload. The performance best practices paper says leave at default. There used to be (and probably still are) other similar examples. All that really means is that Oracle employs humans who produce work in line with their skills and experience and towards the company goals as understood by their management at the time. Given a sufficient timeframe I'm sure that other companies documents also exhibit similar behavior. (and then there's always the old riposte "when the facts change, I change my mind. What do you do?") . The sooner people understand that "best practice" or "recommendation" usually means "common behavior we've seen in reputable places" the better. Or they could read things like ITIL that specifically describe best practices as a moving target and not a goal. On Jun 10, 2013 7:37 PM, "Kevin Closson" <ora_kclosson_at_yahoo.com> wrote:
>
> That MOS note says "highly recommends the use of standard HugePages" but
> I've also seen documentation that says Oracle strongly recommends AMM. Uh,
> ok.
>
>
>
>
> ________________________________
> From: Rich Jesse <rjoralist2_at_society.servebeer.com>
> To: oracle-l_at_freelists.org
> Sent: Thursday, June 6, 2013 7:59 AM
> Subject: Transparent HugePages causing crashes?
>
>
> Hey all,
>
> MOS has a new alert 1557478.1 that says "Because Transparent HugePages are
> known to cause unexpected node reboots and performance problems with RAC,
> Oracle strongly advises to disable the use of Transparent HugePages."
>
> However, I can't find anything searching for issues with THP in all the
> usual places. Is this just a RAC issue? Specific to Oracle instances
> running on later Linux releases?
>
> THP seems more like AIX's 64k medium pages and I was hoping to use them to
> help prevent DBA errors in sizing traditional HugePages.
>
> Anyone using THP?
>
> Rich
>
> --
> http://www.freelists.org/webpage/oracle-l
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Mon Jun 10 2013 - 21:07:37 CEST