Re: Baseline usage?
From: Wolfgang Breitling <breitliw_at_centrexcc.com>
Date: Fri, 26 Sep 2014 15:08:43 -0600
Message-Id: <F399D2B1-D07B-4E59-ABCA-A5F4EE083B8E_at_centrexcc.com>
If the baselined sql runs in 0.03 seconds it may escape capture into AWR. Remember, ASH and thus AWR are based on sampling so if s sql is "too fast" it may not be seen, although if it is executed very frequently that should increase the chance that ASH will notice it. If you want to be sure it is included in ASH, color it.
>> On Sep 26, 2014, at 1:21 PM, Seth Miller <sethmiller.sm_at_gmail.com> wrote:
>>
>> You can have multiple plans in the plan history per sql statement. You can also have multiple baselines per sql statement. You can even have multiple baseline plans enabled and accepted but none of these things means that those plans will be used.
>>
>> Can you post examples of your findings?
>>
>> Seth Miller
>>
>>
Date: Fri, 26 Sep 2014 15:08:43 -0600
Message-Id: <F399D2B1-D07B-4E59-ABCA-A5F4EE083B8E_at_centrexcc.com>
If the baselined sql runs in 0.03 seconds it may escape capture into AWR. Remember, ASH and thus AWR are based on sampling so if s sql is "too fast" it may not be seen, although if it is executed very frequently that should increase the chance that ASH will notice it. If you want to be sure it is included in ASH, color it.
Sent from my iPhone. Typing errors may have occurred.
> On Sep 26, 2014, at 14:43, Andrew Kerber <andrew.kerber_at_gmail.com> wrote: > > Well, it's just a single baseline. But, without the baseline a particular query ran in about 1.3 sec. With the baseline it ran in .03 sec. The AWR shows the latter timing for the query (it gets run thousands of times per hour), but I can't find anywhere else to prove it. There is another query running a few hundred times per hour that was running in about 3 minutes that the baseline should take that about .3 seconds. However, if it uses the baseline it probably doesn't make enough impact to show on the AWR report. I would just like a second method of verifying the baseline is being used. > > Sent from my iPad >
>> On Sep 26, 2014, at 1:21 PM, Seth Miller <sethmiller.sm_at_gmail.com> wrote:
>>
>> You can have multiple plans in the plan history per sql statement. You can also have multiple baselines per sql statement. You can even have multiple baseline plans enabled and accepted but none of these things means that those plans will be used.
>>
>> Can you post examples of your findings?
>>
>> Seth Miller
>>
>>> On Fri, Sep 26, 2014 at 12:57 PM, Andrew Kerber <andrew.kerber_at_gmail.com> wrote: >>> That's what I would have thought, but the AWR shows the queries, the timing on the AWR report indicates that the baseline was used, but the executions number never increases. >>> >>> Sent from my iPad >>> >>>> On Sep 26, 2014, at 11:38 AM, Seth Miller <sethmiller.sm_at_gmail.com> wrote: >>>> >>>> If you mean number of executions, you can query DBA_SQL_PLAN_BASELINES.EXECUTIONS. >>>> >>>> Seth Miller >>>> >>>>> On Fri, Sep 26, 2014 at 11:27 AM, Andrew Kerber <andrew.kerber_at_gmail.com> wrote: >>>>> Does anyone know where we can check and see how often a sql plan baseline is used? >>>>> >>>>> Sent from my iPad-- >>>>> http://www.freelists.org/webpage/oracle-l
>>
-- http://www.freelists.org/webpage/oracle-lReceived on Fri Sep 26 2014 - 23:08:43 CEST