Add latency measures with XDP

measure-analysis/additional-measures.md

-## Packet reception latency
+## Packet transmission latency
 
-Shuttle to A20, no XDP
+### Shuttle to A20
 
-With tracing and timestamps (some overhead):
+#### Measures done with tracing and timestamps (some overhead):
 
-| Latency measured                       |  min   |  avg   |  max   |
-| -------------------------------------- | ------ | ------ | ------ |
-| IRQ -> RX SO_TIMESTAMP                 |   27us |   31us |  136us |
-| RX SO_TIMESTAMP -> Userspace timestamp |   85us |   93us |  247us |
-| IRQ -> Userspace timestamp             |  112us |  124us |  383us |
+**Without XDP:**
 
+| **Latency measured**                   | **min** | **avg** | **max** |
+| -------------------------------------- | ------- | ------- | ------- |
+| IRQ -> RX SO_TIMESTAMP                 |   27us  |   31us  |  136us  |
+| RX SO_TIMESTAMP -> Userspace timestamp |   85us  |   93us  |  247us  |
+| IRQ -> Userspace timestamp             |  112us  |  124us  |  383us  |
 
-With timestamps (little overhead):
+**With XDP:**
 
-| Latency measured                       |  min   |  avg   |  max   |  
-| -------------------------------------- | ------ | ------ | ------ |  
-| Shuttle timestamp -> A20 timestamp     |   88us |   88us |  300us |
-| RX SO_TIMESTAMP (A20)                  |   67us |  172us |  173us |
-| TX SO_TIMESTAMP -> (Shuttle)           |    2us |   18us |   20us |
+IRQ -> XDP_REDIRECT : ~30us (more measures needs to be done)
+
+#### Measures done with timestamps (little overhead):
+
+| **Latency measured**                   |        | **Duration** | **Packets number** | **Interval** | **min** | **avg** |  **max** |  
+| -------------------------------------- | ------ | ------------ | ------------------ | ------------ | ------- | ------  | ------   |  
+| Shuttle timestamp -> A20 timestamp     | XDP    |  2h45        | 50 100 000         | 250us        |   22us  |   24us  |  173us   |
+| Shuttle timestamp -> A20 timestamp     | no XDP |              |                    |              |   88us  |   88us  |  300us   |
+| RX SO_TIMESTAMP (A20)                  | no XDP |              |                    |              |   67us  |  172us  |  173us   |
+| TX SO_TIMESTAMP -> (Shuttle)           | no XDP |              |                    |              |    2us  |   18us  |   20us   |