maria-discuss team mailing list archive

[Laurynas Biveinis <laurynas.biveinis@xxxxxxxxx>]

Sergei, Colin, MariaDB -

>> >> "XtraDB storage engine was upgraded to the 5.6 version. Now one can
>> >> use XtraDB with MariaDB 10.0. Unlike MariaDB 5.5, in 10.0 XtraDB is
>> >> not the default engine, the default is InnoDB, and XtraDB is
>> >> available as a dynamic plugin"
>> >>
>> > XtraDB simply does not compile on all our builders - Percona has
>> > introduced patches that use CPU atomic ops and didn't implement a
>> > fallback for setups where they are not available (like all the rest
>> > of the code does, including InnoDB).
>>
>> Have we reported bugs upstream?
>
> https://bugs.launchpad.net/bugs/1276963
>
>> Do we plan on fixing this ourselves if upstream doesn't?
>
> Not at the moment - that code is quite complex.

In the bug report you mention RHEL 5 with GCC 4.1.2 (presumably on 32
bits). This is one of our supported platforms too, and we solve this
by adding -march=i686 which makes the necessary builtins available.
Would that work for you?

We have another platform-specific addition: thread-local storage
implemented by __thread GCC keyword, which is GNU specific. This is
used to implement the relative XtraDB thread priorities:
http://www.percona.com/doc/percona-server/5.6/performance/xtradb_performance_improvements_for_io-bound_highly-concurrent_workloads.html#relative-thread-scheduling-priorities-for-xtradb.
On non-Linux plaftorms the feature should compile but should be
silently disabled, that is, setting innodb_sched_priority_* options
are no-ops. How big is this an issue for you?

-- 
Laurynas