add stream bps config option

docs/config.md

@@ -550,11 +550,19 @@ Attribute | Description | Default
 `priority` | IPv4 TOS / IPv6 TC | 0
 `vlan-priority` | VLAN priority | 0 
 `length` | Layer 3 (IP + payload) traffic length (76 - 1500) | 128
-`pps` | Stream traffic rate in packets per second | 1 
+`pps` | Stream traffic rate in packets per second | 1
+`bps` | Stream traffic rate in bits per second (layer 3) | 
 `network-ipv4-address` | Overwrite network interface IPv4 address | 
 `network-ipv6-address` | Overwrite network interface IPv6 address | 
 `threaded` | Run those streams in separate threads | false
 
 For L2TP downstream traffic the IPv4 TOS is applied to the outer IPv4 and inner IPv4 header.
 
+The `pps` option has priority over `bps` where second is only a helper to calculate the `pps` 
+based on given `bps` and `length`. 
+
+With threading enabled, those streams will be started in a dedicated thread per flow. This
+means one thread per session and stream direction. A threaded , bidirectional stream assigned 
+to 10 sessions will therefore run in 20 threads. 
+
 **WARNING**: The threading support is experimental and should be used with caution! 

docs/streams.md

@@ -7,8 +7,9 @@ Traffic streams allow to test QoS using BNG Blaster.
 ```json
 {
     "interfaces": {
-        "tx-interval": 1,
-        "rx-interval": 1,
+        "tx-interval": 0.1,
+        "rx-interval": 0.1,
+        "io-slots": 2048,
         "network": {
             "interface": "eth2",
             "address": "10.0.0.1",
@@ -206,7 +207,7 @@ The `rx-outer-vlan-pbit` might be wrong depending on network interface driver an
 optional VLAN offloading. 
 
 The measured `rx-delay-nsec-min/max` depends also on the actual test environment 
-and maximum host send delay.
+and maximum host IO delay.
 
 ## Start/Stop Session Stream Information
 

src/bbl_config.c

@@ -311,6 +311,7 @@ static bool
 json_parse_stream (bbl_ctx_s *ctx, json_t *stream, bbl_stream_config *stream_config) {
     json_t *value = NULL;
     const char *s = NULL;
+    double bps;
 
     if (json_unpack(stream, "{s:s}", "type", &s) == 0) {
         if (strcmp(s, "ipv4") == 0) {
@@ -385,8 +386,18 @@ json_parse_stream (bbl_ctx_s *ctx, json_t *stream, bbl_stream_config *stream_con
             return false;
         }
     } else {
-        stream_config->pps = 1;
+        /* pps config has priority over bps */
+        value = json_object_get(stream, "bps");
+        if (value) {
+            bps = json_number_value(value);
+            if(!bps) {
+                fprintf(stderr, "JSON config error: Invalid value for stream->bps\n");
+                return false;
+            }
+            stream_config->pps = bps / (stream_config->length * 8);
+        }
     }
+    if(!stream_config->pps) stream_config->pps = 1;
 
     if (json_unpack(stream, "{s:s}", "network-ipv4-address", &s) == 0) {
         if(!inet_pton(AF_INET, s, &stream_config->ipv4_network_address)) {

src/bbl_stream.c

@@ -758,7 +758,7 @@ bbl_stream_add(bbl_ctx_s *ctx, bbl_access_config_s *access_config, bbl_session_s
                     timer_add_periodic(&ctx->timer_root, &stream->timer, config->name, timer_sec, timer_nsec, stream, bbl_stream_tx_job);
                 }
                 timer_add_periodic(&ctx->timer_root, &stream->timer_rate, "Rate Computation", 1, 0, stream, bbl_stream_rate_job);
-                LOG(DEBUG, "Traffic stream %s added in upstream with timer %lu sec %lu nsec\n", config->name, timer_sec, timer_nsec); 
+                LOG(DEBUG, "Traffic stream %s added in upstream with %u PPS (timer: %lu sec %lu nsec)\n", config->name, config->pps, timer_sec, timer_nsec); 
             }
             if(config->direction & STREAM_DIRECTION_DOWN) {
                 stream = calloc(1, sizeof(bbl_stream));
@@ -792,7 +792,7 @@ bbl_stream_add(bbl_ctx_s *ctx, bbl_access_config_s *access_config, bbl_session_s
                     timer_add_periodic(&ctx->timer_root, &stream->timer, config->name, timer_sec, timer_nsec, stream, bbl_stream_tx_job);
                 }
                 timer_add_periodic(&ctx->timer_root, &stream->timer_rate, "Rate Computation", 1, 0, stream, bbl_stream_rate_job);
-                LOG(DEBUG, "Traffic stream %s added in downstream with timer %lu sec %lu nsec\n", config->name, timer_sec, timer_nsec); 
+                LOG(DEBUG, "Traffic stream %s added in downstream with %u PPS (timer %lu sec %lu nsec)\n", config->name, config->pps, timer_sec, timer_nsec); 
             }
             timer_smear_bucket(&ctx->timer_root, timer_sec, timer_nsec);
         }