queue classic not thread safe about queue_classic HOT 3 CLOSED

Can you provide a sample for this? We are facing a similar issue and wanted to tackle this also with better connection handling when running our own daemon with threaded workers. Thanks.

from queue_classic.

This results in this single connection adapter being re-used across all threads for all subsequent enqueue calls.

Is this a problem? pg gem is quite thread-safe, as its underlying libpq, connections created in one thread can be reused in another. AFAIK, activerecord pool works this way: thread returns connection to pool, another thread can take it. Moreover, queue_classic has mutex for queries.

There's possibility of building libpq without thread safety, you can check PG::Connection.isthreadsafe, but AFAIK this is rare.

Second, it is not the connection for the active thread and may actually be being used by another thread if that thread has checked the same one out of the pool.

What's the problem with pool? Queue_classic takes one connection from the pool and never checks out it back. Connections can be safely reused across threads.

What error messages you get? I encountered protocol errors because of reused PG connections, but in forked web server, because there were multiple PG::Connection instances in different processes using single underlying socket created prior to to forking.

from queue_classic.

Closing as this is stale; @gfodor if you can share the code, I'd def check it out.

from queue_classic.