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From:Morgan Tocker Date:July 14 2014 6:31pm
Subject:Re: Query time taken on disk
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Hi Satendra,

On Jul 14, 2014, at 3:48 AM, Satendra <stdranwl@stripped> wrote:

> Hi there, I'm struggling to find the total time taken by a database query
> on the disk? As I understand when a database query start execution it takes
> some time inside the database engine & some time to seek the result from
> disk (if that is not in cache/buffer)
> 
> Can anybody from the group please suggest any clue about the execution time
> on the disk?

I have a performance_schema example demonstrating total IO wait time for a workload:
http://www.tocker.ca/2014/02/18/todays-practical-use-case-for-performance-schema.html

To prepare this data non-aggregated (per-query) is always a little bit difficult:
- With select statements there is read ahead.
- With write statements there is redo logging (which is grouped together with other
statements).

Maybe someone else on the list has better ideas on how to accommodate this?

- Morgan
Thread
Query time taken on diskSatendra14 Jul 2014
  • Re: Query time taken on diskReindl Harald14 Jul 2014
    • Re: Query time taken on diskKeith Murphy14 Jul 2014
  • Re: Query time taken on diskMorgan Tocker14 Jul 2014
  • Re: Query time taken on diskgreg.lane14 Jul 2014