After apply this change:

diff --git apisix/plugins/traffic-split.lua apisix/plugins/traffic-split.lua
index eb7a2028..3d5e7d8f 100644
--- apisix/plugins/traffic-split.lua
+++ apisix/plugins/traffic-split.lua
@@ -315,8 +315,7 @@ function _M.access(conf, ctx)
     end

     local route_upstream_id = ctx.matched_route.value.upstream_id
-    local rr_up, err = lrucache(weighted_upstreams, nil, new_rr_obj, weighted_upstreams,
-                                route_upstream_id)
+    local rr_up, err = new_rr_obj(weighted_upstreams, route_upstream_id)
     if not rr_up then
         core.log.error("lrucache roundrobin failed: ", err)
         return 500

many test cases are failed. Look like new_rr_obj corrupts the route's configuration. This may happen once the cache is evicted.

Look like new_rr_obj corrupts the route's configuration. This may happen once the cache is evicted.

yes, according to my understanding, I think the design idea of traffic-split itself is to achieve the goal by corrupts the route's configuration.

take a look at

There should be a way to do the same thing without corrupting the data. Otherwise once the cache is evicted we will be in trouble.

There should be a way to do the same thing without corrupting the data. Otherwise once the cache is evicted we will be in trouble.

This PR does not do this work. If needed, we should open another issue to discuss it, as it would involve refactoring the plugin's implementation logic.