[Mesa-dev] [RFC] ralloc: use jemalloc for faster GLSL compilation

[Emil Velikov]

On 29 September 2016 at 11:48, Marek Olšák <maraeo at gmail.com> wrote:
> On Thu, Sep 29, 2016 at 11:20 AM, Nicolai Hähnle <nhaehnle at gmail.com> wrote:
>> On 28.09.2016 18:49, Marek Olšák wrote:
>>>
>>> From: Marek Olšák <marek.olsak at amd.com>
>>>
>>> More info about jemalloc:
>>>    https://github.com/jemalloc/jemalloc/wiki/History
>>>
>>> Average from 3 takes compiling Alien Isolation shaders from GLSL to GCN
>>> bytecode:
>>>    glibc:    17.183s
>>>    jemalloc: 15.558s
>>>    diff:     -9.5%
>>>
>>> The diff is -10.5% for a full shader-db run.
>>> ---
>>>
>>> TODO: The jemalloc dependency should be added to configure.ac before this.
>>>
>>> We can probably redirect all malloc/calloc/realloc/free calls in Mesa to
>>> jemalloc. We can either use _mesa_jemalloc, etc. everywhere or we can
>>> redirect calls to jemalloc using #define malloc _mesa_jemalloc, etc.
>>>
>>> Right now, I just use: export LDFLAGS=-ljemalloc
>>
>>
>> Sounds good to me. It should probably be a configurable option, defaulting
>> to jemalloc and failing if not available unless explicitly disabled.
>
> If it was a configurable option, almost nobody would use it. Let's
> make it mandatory.
>
This combined with ...

>>
>> On the Gallium side of things, switching to jemalloc could be pretty
>> straightforward via the macros in u_memory.h, once we know that they're
>> actually used consistently (which we currently don't -- it would be nice to
>> know how jemalloc and glibc malloc react when the calls are mixed).
>
> Redefining malloc/calloc/realloc/free/posix_memalign for all Mesa code
> would be more robust.
>
... this doesn't is not a wise move.

Don't force jemalloc onto everyone without having an explicit ACK from
a wide audience, please ? Considering the static/shared link (or w/o
jemalloc all together) distributions will have their
preferences/policies which won't align with my/your view.

Thanks
Emil