Linux Network Stack Queues

Question

I am debugging some network driver under Linux. At some point in this driver, there is the netif_stop_queue () function. It stops sending packets to the kernel to my driver, and that's fine.

I wonder how long the kernel can queue these packets until it starts throwing them. Is this the txqueuelen parameter in ifconfig, which shows how many packets the interface can have in the queue or is there another queue in the kernel?

Answer 1

The unsigned long tx_queue_len field in the net_device netdevice.h structure , line 1143 controls the maximum number of frames that can be queued on the device transfer queue

And yes, this is the same parameter in ifconfig. You can set the queue length with:

ifconfig <interface> txqueuelen <size> Ex: ifconfig eth0 txqueuelen 10000