[Tarantool-patches] [PATCH 1/1] fiber: extend max fiber name length to 255

[Cyrill Gorcunov]

On Sat, Mar 14, 2020 at 06:32:01PM +0100, Vladislav Shpilevoy wrote:
> Besides, most of the users don't use long names. So for them
> it would be overkill to allocate such a big name memory for each
> fiber.

Look, currently all fiber data (including name) placed in one
continious memory area. After the patch the name gonna be "somewhere",
moreover this "somewhere" is completely unpredictable and access
to it will cause (i'm pretty sure) useless cache drains. If we
really need to support long names then we better make some union
which would carry both, short 32 byte names or long dynamically
allocated names.

And no, the statement "heap allocation doesn't affect anyone"
is simply wrong, this is not how memory works on a low level
(otherwise we wouldn't use "small" helpers at all, plain libc
malloc would fit us without a problem :).