This adds the sample fetch 'be_conn_free([<backend>])'. This sample fetch
provides the total number of unused connections across available servers
in the
specified backend.
---
doc/configuration.txt | 15 ++++++++++++++-
src/backend.c | 38 ++++++++++++++++++++++++++++++++++++++
2 files changed, 52 insertions(+), 1 deletion(-)
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 48b69a5bd..b5c093e15 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -13682,7 +13682,20 @@ be_conn([<backend>]) : integer
possibly including the connection being evaluated. If no backend name is
specified, the current one is used. But it is also possible to check another
backend. It can be used to use a specific farm when the nominal one is full.
- See also the "fe_conn", "queue" and "be_sess_rate" criteria.
+ See also the "fe_conn", "queue", "be_conn_free", and "be_sess_rate" criteria.
+
+be_conn_free([<backend>]) : integer
+ Returns an integer value corresponding to the number of available connections
+ across available servers in the backend. Queue slots are not included. Backup
+ servers are also not included, unless all other servers are down. If no
+ backend name is specified, the current one is used. But it is also possible
+ to check another backend. It can be used to use a specific farm when the
+ nominal one is full. See also the "be_conn" and "connslots" criteria.
+
+ OTHER CAVEATS AND NOTES: at this point in time, the code does not take care
+ of dynamic connections. Also, if any of the server maxconn, or maxqueue is 0,
+ then this fetch clearly does not make sense, in which case the value returned
+ will be -1.
be_sess_rate([<backend>]) : integer
Returns an integer value corresponding to the sessions creation rate on the
diff --git a/src/backend.c b/src/backend.c
index 1aadca590..c26304a2d 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -1792,6 +1792,43 @@ smp_fetch_be_conn(const struct arg *args, struct sample *smp, const char *kw, vo
return 1;
}
+/* set temp integer to the number of available connections across available
+ * servers on the backend.
+ * Accepts exactly 1 argument. Argument is a backend, other types will lead to
+ * undefined behaviour.
+ */
+static int
+smp_fetch_be_conn_free(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+ struct server *iterator;
+ struct proxy *px;
+
+ smp->flags = SMP_F_VOL_TEST;
+ smp->data.type = SMP_T_SINT;
+ smp->data.u.sint = 0;
+
+ for (iterator = args->data.prx->srv; iterator; iterator = iterator->next) {
+ if (iterator->cur_state == SRV_ST_STOPPED)
+ continue;
+
+ px = iterator->proxy;
+ if (!srv_currently_usable(iterator) || ((iterator->flags & SRV_F_BACKUP) &&
+ (px->srv_act ||
+ (iterator != px->lbprm.fbck && !(px->options & PR_O_USE_ALL_BK)))))
+ continue;
+
+ if (iterator->maxconn == 0) {
+ /* configuration is stupid */
+ smp->data.u.sint = -1; /* FIXME: stupid value! */
+ return 1;
+ }
+
+ smp->data.u.sint += (iterator->maxconn - iterator->cur_sess);
+ }
+
+ return 1;
+}
+
/* set temp integer to the total number of queued connections on the backend.
* Accepts exactly 1 argument. Argument is a backend, other types will lead to
* undefined behaviour.
@@ -1897,6 +1934,7 @@ static int sample_conv_nbsrv(const struct arg *args, struct sample *smp, void *p
static struct sample_fetch_kw_list smp_kws = {ILH, {
{ "avg_queue", smp_fetch_avg_queue_size, ARG1(1,BE), NULL, SMP_T_SINT, SMP_USE_INTRN, },
{ "be_conn", smp_fetch_be_conn, ARG1(1,BE), NULL, SMP_T_SINT, SMP_USE_INTRN, },
+ { "be_conn_free", smp_fetch_be_conn_free, ARG1(1,BE), NULL, SMP_T_SINT, SMP_USE_INTRN, },
{ "be_id", smp_fetch_be_id, 0, NULL, SMP_T_SINT, SMP_USE_BKEND, },
{ "be_name", smp_fetch_be_name, 0, NULL, SMP_T_STR, SMP_USE_BKEND, },
{ "be_sess_rate", smp_fetch_be_sess_rate, ARG1(1,BE), NULL, SMP_T_SINT, SMP_USE_INTRN, },
