Rechercher dans le manuel MySQL
C.8 Restrictions on Performance Schema
The Performance Schema avoids using mutexes to collect or produce
data, so there are no guarantees of consistency and results can
sometimes be incorrect. Event values in
performance_schema tables are nondeterministic
and nonrepeatable.
If you save event information in another table, you should not
assume that the original events will still be available later. For
example, if you select events from a
performance_schema table into a temporary
table, intending to join that table with the original table later,
there might be no matches.
mysqldump and BACKUP
DATABASE ignore tables in the
performance_schema database.
Tables in the performance_schema database
cannot be locked with LOCK TABLES, except the
setup_ tables.
xxx
Tables in the performance_schema database
cannot be indexed.
Tables in the performance_schema database are
not replicated.
The types of timers might vary per platform. The
performance_timers table shows which
event timers are available. If the values in this table for a
given timer name are NULL, that timer is not
supported on your platform.
Instruments that apply to storage engines might not be implemented for all storage engines. Instrumentation of each third-party engine is the responsibility of the engine maintainer.
Document created the 26/06/2006, last modified the 26/10/2018
Source of the printed document:https://www.gaudry.be/en/mysql-rf-performance-schema-restrictions.html
The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.
References
These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.
