Performance optimization #632
Conversation
…le connection and now we have almost linear scalability on 2K-32K connections; also remove old debug prints
…comment by results of benchmarks and profiling: we have serious performance issues somewhere in cache
| * Queue the cache work if it must be server by remote node only. | ||
| * Otherwise we can do everything right now on local CPU. | ||
| */ | ||
| if (likely(req->node == numa_node_id())) { |
There was a problem hiding this comment.
It appears that req->node is not really needed and can be eliminated from TfwHttpReq{} structure. It's only used in the call to tfw_cache_sched_cpu() below, and it can easily be replaced by a local variable here (say, nodeid) that can be passed to that function to get the cpu. The only other place where it's used is tfw_cache_add() in a fresh new BUG_ON() that has only appeared in this patch and was not there before.
| } | ||
| else { | ||
| cache_req_process_node(req, action); | ||
| } |
There was a problem hiding this comment.
Actually, this whole code block doesn't require curly braces as all statements are single-line.
There was a problem hiding this comment.
Usually we use curly braces in comples if-else statements: https://github.com/tempesta-tech/linux-4.1.27-tfw/blob/master/Documentation/CodingStyle#L141
| if (ret) | ||
| return tfw_http_send_404(req); | ||
| else | ||
| return tfw_http_send_200(req); |
There was a problem hiding this comment.
I know that this is the way it was, but perhaps it can be changed to something like this?
return ret
? tfw_http_send_404(req)
: tfw_http_send_200(req);| default: | ||
| return tfw_http_send_403(req); | ||
| /* | ||
| * Queue the cache work if it must be server by remote node only. |
There was a problem hiding this comment.
Queue the cache work only when it must be served by a remote node.
Do not queue cache work for local CPU: 25% better performance on single connection and now we have almost linear scalability on 2K-32K connections; also remove old debug prints