Re: using software TSO on non-TSO capable netdevices
From: David Miller <davem@davemloft.net>
Date: 2008-07-31 12:35:16
From: David Miller <davem@davemloft.net>
Date: 2008-07-31 12:35:16
From: Lennert Buytenhek <redacted> Date: Thu, 31 Jul 2008 14:25:41 +0200
At this point things seem to be CPU limited at the sender again. E.g. by simply dropping IRQF_SAMPLE_RANDOM from mv643xx_eth.c (the driver used on the sender), throughput jumps to ~108 MiB/s, and I get:
...
Putting the 5 * mss_now nagle hack back in doesn't seem to change the gso_size distribution anymore at this point, and it doesn't change the numbers much:
...
The throughput with software GSO off again seems to be about ~93 MiB/s:
So I would conclude that at the moment we should just do the software GSO enabling thing (with the recent suggestions made by Herbert) and for the time being the nagle hack isn't something to consider closely.