tree f53f59f221bf40f8155fa813b395600ac5f7e7f7
parent 49e1080765627db53eb10d18a510613e92d3ed7a
author Willy Tarreau <w@1wt.eu> 1614851274 +0100
committer Willy Tarreau <w@1wt.eu> 1615385476 +0100
encoding latin1

MINOR: server: move actconns to the per-thread structure

The actconns list creates massive contention on low server counts because
it's in fact a list of streams using a server, all threads compete on the
list's head and it's still possible to see some watchdog panics on 48
threads under extreme contention with 47 threads trying to add and one
thread trying to delete.

Moving this list per thread is trivial because it's only used by
srv_shutdown_streams(), which simply required to iterate over the list.

The field was renamed to "streams" as it's really a list of streams
rather than a list of connections.

(cherry picked from commit d4e78d873cecf9938885c90e736f8b761a35fb55)
[wt: for 2.3 and older, this is a simplified version. We don't want to
 touch all the server initialization code and sequence with the risks
 of causing new trouble, so instead we declare actconns as an array
 of the maximum number of supported threads, this will eat a bit more
 memory on smaller machines but will remain safe. Those building with
 MAX_THREADS close or equal to their target number of threads may even
 save some RAM compared to 2.4. The only servers not initialized via
 new_server() are the two Lua socket servers, and they've been handled
 here]
Signed-off-by: Willy Tarreau <w@1wt.eu>