[lxc-devel] [PATCH 1/2] Add lxc.network.mtu configuration

[Daniel Lezcano]

Ryousei Takano wrote:
> Hi Daniel,
>
> On Mon, Mar 23, 2009 at 7:04 AM, Daniel Lezcano <dlezcano at fr.ibm.com> wrote:
>
> [snip]
>
>   
>> I played a bit with the patch and noticed the mtu is only set for one side
>> of the veth, the one attached to the bridge, so I wrote a patch on top of
>> your patch to set both side and applied both patches in the git tree. Maybe,
>> that will increase the throughput performances a little more.
>>
>>     
> Thanks for merging my patch.
> I checked lxc-0.6.1 and your commit 75d09f83b82f35a610f4922e06ad897692062fab
> (set mtu for netdev).
>
> I found a problem of the MTU size of br0.  In the current code,
> device_set_mtu() is
> called after bridge_attach(), so the MTU size of br0 is set to the
> default MTU size
> of veth0 (i.e., 1500 bytes).
> This causes performance degradation as I reported.
>
> We need to modify to call device_set_mtu() before bridge_attach()
Oups, right.
Good catch :)

Will fix it.