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

[Marek Olšák]

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.

>
> 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.

Marek