[MEDIUM] differentiate between generic LB params and map-specific ones
Since the introduction of server weights, all load balancing algorithms
relied on a pre-computed map. Incidently, quite a bunch of map-specific
parameters were used at random places in order to get the number of
servers or their total weight. It was not architecturally acceptable
that optimizations for the map computation had impact on external parts.
For instance, during this cleanup it was found that a backend weight was
seen as 1 when only the first backup server is used, whatever its weight.
This cleanup consists in differentiating between LB-generic parameters,
such as total weights, number of servers, etc... and map-specific ones.
The struct proxy has been enhanced in order to make it easier to later
support other algorithms. The recount_servers() function now also
updates generic values such as total weights so that it's not needed
anymore to call recalc_server_map() when weights are needed. This
permitted to simplify some code which does not need to know about map
internals anymore.
diff --git a/include/types/proxy.h b/include/types/proxy.h
index ecc4d9c..03f9601 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -54,7 +54,7 @@
#define PR_MODE_HTTP 1
#define PR_MODE_HEALTH 2
-/* values for proxy->map_state */
+/* values for proxy->lbprm.map.state */
#define PR_MAP_RECALC (1 << 0)
/* flag values for proxy->cap. This is a bitmask of capabilities supported by the proxy */
@@ -78,13 +78,21 @@
struct list acl; /* ACL declared on this proxy */
struct list block_cond; /* early blocking conditions (chained) */
struct list switching_rules; /* content switching rules (chained) */
- int map_state; /* PR_MAP_RECALC */
struct server *srv; /* known servers */
int srv_act, srv_bck; /* # of running servers */
- int tot_wact, tot_wbck; /* total weights of active and backup servers */
- struct server **srv_map; /* the server map used to apply weights */
- int srv_map_sz; /* the size of the effective server map */
- int srv_rr_idx; /* next server to be elected in round robin mode */
+
+ struct {
+ int tot_wact, tot_wbck; /* total effective weights of active and backup servers */
+ int tot_weight; /* total effective weight of servers participating to LB */
+ int tot_used; /* total number of servers used for LB */
+ int wmult; /* ratio between user weight and effective weight */
+ struct {
+ struct server **srv; /* the server map used to apply weights */
+ int rr_idx; /* next server to be elected in round robin mode */
+ int state; /* PR_MAP_RECALC */
+ } map; /* LB parameters for map-based algorithms */
+ } lbprm; /* LB parameters for all algorithms */
+
char *cookie_name; /* name of the cookie to look for */
int cookie_len; /* strlen(cookie_name), computed only once */
char *url_param_name; /* name of the URL parameter used for hashing */