Man pages matching name gearman_client_set_memory_allocators in section 3:

gearman_client_set_memory_allocators.3.en	debian 10 / libgearman-dev
gearman_client_set_memory_allocators.3.en	debian 11 / libgearman-dev
gearman_client_set_memory_allocators.3.en	debian 12 / libgearman-dev