Could relay cache be shared across php cli processes?

[dorrogeray]

Would it be technically possible to share the relay cache not just between php-fpm processes, but also between php cli processes? Using something like shared system memory, where some id would be provided in relay extension configuration to identify such shared memory? Therefore you could have 10 php-fpm processes sharing memory with 10 php cli workers, or have them configured to use separate memory blocks (1 for workers and 1 for php-fpm processes).

Asking because it would be really nice if cli workers could also leverage local relay cache.

[michael-grunder]

Yes, it is technically possible.

Relay uses a bespoke heap allocator (a malloc-like API analog) that operates against mmap'ed shared memory. To make this work with System V shared memory we would need to add a mechanism to turn offsets into the appropriate virtual memory address for each attached client (as they'll likely map to different virtual addresses).