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Diffstat (limited to 'docs/CANBUS_Troubleshooting.md')
| -rw-r--r-- | docs/CANBUS_Troubleshooting.md | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/docs/CANBUS_Troubleshooting.md b/docs/CANBUS_Troubleshooting.md index 1464c85e..de0deaf7 100644 --- a/docs/CANBUS_Troubleshooting.md +++ b/docs/CANBUS_Troubleshooting.md @@ -81,15 +81,15 @@ link show can0`. It should report a bunch of text including the snippet `qlen 128`. If one sees something like `qlen 10` then it indicates the CAN device has not been properly configured. -It is not recommended to use a `txqueuelen` significantly larger than -128. A CAN bus running at a frequency of 1000000 will typically take -around 120us to transmit a CAN packet. Thus a queue of 128 packets is -likely to take around 15-20ms to drain. A substantially larger queue -could cause excessive spikes in message round-trip-time which could -lead to unrecoverable errors. Said another way, Klipper's application -retransmit system is more robust if it does not have to wait for Linux -to drain an excessively large queue of possibly stale data. This is -analogous to the problem of +It is not recommended to use a `txqueuelen` significantly larger +than 128. A CAN bus running at a frequency of 1000000 will typically +take around 120us to transmit a CAN packet. Thus a queue of 128 +packets is likely to take around 15-20ms to drain. A substantially +larger queue could cause excessive spikes in message round-trip-time +which could lead to unrecoverable errors. Said another way, Klipper's +application retransmit system is more robust if it does not have to +wait for Linux to drain an excessively large queue of possibly stale +data. This is analogous to the problem of [bufferbloat](https://en.wikipedia.org/wiki/Bufferbloat) on internet routers. |