MySQL Bugs: #71303: Manual page on P_S build configuration does not provide enough details

Bug #71303	Manual page on P_S build configuration does not provide enough details
Submitted:	5 Jan 2014 16:00	Modified:	3 Mar 2016 23:20
Reporter:	Valeriy Kravchuk	Email Updates:
Status:	Won't fix	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	5.6	OS:	Any
Assigned to:	Paul DuBois	CPU Architecture:	Any
Tags:	build configuration, missing manual, performance_schema, PFS_GROUP_BUFFER_SYNC

Description:
This manual page, http://dev.mysql.com/doc/refman/5.6/en/performance-schema-build-configuration.html, mentions only two build time defines:

-DWITH_PERFSCHEMA_STORAGE_ENGINE=1
-DWITHOUT_PERFSCHEMA_STORAGE_ENGINE=1

While looking at the source code I see that some PERFORMANCE_SCHEMA related details (including instrumentation available) seem to depend on some other build time defines, that may be defined to different values:

UNIV_PFS_MUTEX
UNIV_PFS_RWLOCK
PFS_GROUP_BUFFER_SYNC

With all three above defined, for example, it looks like we may get additional instrumentation for individual InnoDB blocks' mutexes and rwlocks... This may be useful for cases like Bug #68079.

How to repeat:
Try to find something about PFS_GROUP_BUFFER_SYNC in the manual, like with Google search for the following:

site:dev.mysql.com PFS_GROUP_BUFFER_SYNC

Note zero hits, go cry or read the code.

Suggested fix:
Make sure all build time options/defines related to PERFORMANCE_SCHEMA are clearly documented in the manual, at http://dev.mysql.com/doc/refman/5.6/en/performance-schema-build-configuration.html or elsewhere.

Hello Valeriy,

Thank you for the bug report.

Thanks,
Umesh

From the InnoDB developers:

UNIV_PFS_MUTEX  and  UNIV_PFS_RWLOCK:
Defined whenever the server is compiled with the -DWITH_PERFSCHEMA_STORAGE_ENGINE option.

PFS_GROUP_BUFFER_SYNC:
Disabled by default. The only way to enable it is by removing the line which defines PFS_SKIP_BUFFER_MUTEX_RWLOCK in storage/innobase/include/sync0sync.h. Seems to be no compiler flags to enable or disable the above mentioned symbol.