ASH browser doesn't show all period

Toad beta 12.7..0.76, Oracle 11.2.0.3

ASH browser shows only part of data-obviously data are not missing (ASH buffer is still full) but somehow ASH browser is not using that.

From ASH browser:

ASH Report for the same time:

ash_oracle_interface.jpeg

All other data are shorten as well in ASH browser.

Brg

Damir

By default it shows the whole range of what is found in v$active_session_history or dba_hist_active_sess_history. I do not know if this range will correspond exactly with what you see in Oracle’s ASH report.

There are a few ways to narrow the range in Toad’s ASH Browser - one is to drag a rectangle in the chart to zoom it. You can undo the zoom by dragging a rectangle up and out of the top left corner (or just hitting refresh). The other way to narrow the range is to use the filter button at the top of the window. Also, in the filter dialog, notice that you can configure the ASH report to use v$active_session_history (which has more frequent data samples, but only the most recent data) or BDA_HIST_ACTIVE_SESS_HISTORY (less frequent data samples, but over a greater time range).

Hi John,

Problem is that I miss all data from midnight until 11:20 (somewhere) and drill down doesn't show then as well.

Filter is totally disable (no start, no stop ranges or any other ones). Before there was one but it was unchecked ...so now all range should be shown ... but doesn't.

Something somewhere is somehow remember wrong ... have no clue what

Run this query in the editor. This is the maximum possible range of data that the ASH Browser can show you.

select min(sample_time),

max(sample_time)

from v$active_session_history

John,

Looks that there are no ASH data:

16:14:47 >select min(sample_time),
16:14:48 2 max(sample_time)
16:14:48 3 from v$active_session_history ;

MIN(SAMPLE_TIME) MAX(SAMPLE_TIME)


15-JUN-15 12.14.04.672 PM 15-JUN-15 04.14.49.519 PM

Elapsed: 00:00:00.89
16:14:50 >

What confused me was picture ASH report (run few hours ago) where is stated that active_history_session data are used …but now I see that it is AWR and ASH at the end …

Thx for clear up this things

Brg

Damir

What do you mean there is no data? It looks like you have over 2.5 hours of it. Looking at your ASH Report output, it appears that the ASH report uses data from both v$active_session_history AND DBA_HIST_ACTIVE_SESS_HISTORY. In Toad, you can use the filter to choose between the two.

Oops make 4 hours! From 12:14 to 4:14. :slight_smile:

John,

You said. “. In Toad, you can use the filter to choose between the two.”

Could you please explain what did you think by this?

In mine case, exactly mixing turned me to wrong path…

Brg

Damir

Could you please explain what did you think by this?

Are you asking why we did this? Well, Oracle gives two possible data sources for ASH data, so in Toad, I wanted you to be able to use whichever one you want.

In mine case, exactly mixing turned me to wrong path...

Oracle mixes them in the ASH Report. Toad never mixes them. It seems better to me to not mix them, since there is some overlap, and they have different frequency samples.

John

Could you please then explain picture taken from Toad (as stated before) in first mail:

So I find here mixing data in 100% way.

For me it would be best if user cannot choose in ASH browser any value that is outside scope of ASH buffer.

:slight_smile:

Oracle generates that report, not Toad. We just make calls to dbms_workload_repository.ASH_report_html or dbms_workload_repository.ASH_report_text.

Ok…so what did you mean by:

“Toad never mixes them. It seems better to me to not mix them, since there is some overlap, and they have different frequency samples.”

Brg

Damir

Right. Sorry for the confusion. :slight_smile:

Oops… I guess I misread that last message of yours. v$active_session_history collects data more frequently than DBA_HIST_ACTIVE_SESS_HISTORY. For me, I see v$active_session_history samples every second, and they are about once every 10 minutes in DBA_HIST_ACTIVE_SESS_HISTORY.

Also, DBA_HIST_ACTIVE_SESS_HISTORY usually has data over a longer time range. I have months of data in DBA_HIST_ACTIVE_SESS_HISTORY and just a few hours of data in v$active_session_history.