[dpdk-dev] [PATCH] examples/l3fwd-power: fix Rx descriptor size

Pablo de Lara pablo.de.lara.guarch at intel.com
Wed Apr 26 13:29:52 CEST 2017


L3fwd power app monitors the RX queues to see if the polling frequency
should be adjusted (the busier the queue, the higher the frequency).
The app uses several thresholds in the ring to determine the frequency,
being 96 the highest one, when frequency should be highest.

The problem is that the difference between this value and the ring size
is not big enough (128 - 96 = 32 descriptors), which means that
if the descriptors are not replenished quick enough, queue might
not be busy, but the app would think that it is, because 96th descriptor
is set.

Therefore, by increasing this gap (increasing the RX ring size),
we make sure that this false measurement will not happen.

Fixes: b451aa39db31 ("examples/l3fwd-power: use DD bit rather than RX queue count")
Cc: stable at dpdk.org

Signed-off-by: Pablo de Lara <pablo.de.lara.guarch at intel.com>
---
 examples/l3fwd-power/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/l3fwd-power/main.c b/examples/l3fwd-power/main.c
index ec40a17..7a8e1cd 100644
--- a/examples/l3fwd-power/main.c
+++ b/examples/l3fwd-power/main.c
@@ -147,7 +147,7 @@
 /*
  * Configurable number of RX/TX ring descriptors
  */
-#define RTE_TEST_RX_DESC_DEFAULT 128
+#define RTE_TEST_RX_DESC_DEFAULT 512
 #define RTE_TEST_TX_DESC_DEFAULT 512
 static uint16_t nb_rxd = RTE_TEST_RX_DESC_DEFAULT;
 static uint16_t nb_txd = RTE_TEST_TX_DESC_DEFAULT;
-- 
2.7.4



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