On 22/01/14 01:29, cmsv wrote:
On 01/21/2014 07:20 PM, Antonio Quartulli wrote:
On 22/01/14 01:14, cmsv wrote:
On 01/21/2014 07:06 PM, Antonio Quartulli wrote:
On 22/01/14 01:00, Antonio Quartulli wrote:
On 21/01/14 21:01, cmsv wrote:
Yes i understand that but it keeps on increasing. [ 28.600000] batman_adv: bat0: The MTU of interface adhoc0 is too small (1546) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
Have you tried applying this patch before testing it once again?
http://git.open-mesh.org/batman-adv.git/commit/746d6436f88899a79c1cb3b27af06...
Actually this patch is already part of the batman-adv package in openwrt. Therefore the question turns in: did you update the batman-adv package before performing your second test?
the second test was done today and yesterday's i updated bataman-adv.
Yes but we are creating confusion.
Maybe. Lets see.
In the second test you *enabled* network coding, therefore it is normal that the overhead grew up. This happens because NC uses more bytes for its header.
In both tests NC was enabled. I have NC enabled by default before and after the update. In fact is all tests NC is enabled by default and i undestand the increase to 1546 but to 1560 it surprised me. Should i still see the increase to 1560 or should it stayed at 1546 which would be 1532 ?
[Please don't remove the batman-adv mailing list from the CC field.]
The first test you have performed was without the patch that fixes the value reported in that message.
Now that the patch is applied you have to see 1560 when NC is enabled and 1532 when it is disabled.
Can you confirm?
cheers,
inline:
On 01/21/2014 07:31 PM, Antonio Quartulli wrote:
On 22/01/14 01:29, cmsv wrote:
On 01/21/2014 07:20 PM, Antonio Quartulli wrote:
On 22/01/14 01:14, cmsv wrote:
On 01/21/2014 07:06 PM, Antonio Quartulli wrote:
On 22/01/14 01:00, Antonio Quartulli wrote:
On 21/01/14 21:01, cmsv wrote: > Yes i understand that but it keeps on increasing. > [ 28.600000] batman_adv: bat0: The MTU of interface adhoc0 is too > small (1546) to handle the transport of batman-adv packets. Packets > going over this interface will be fragmented on layer2 which could > impact the performance. Setting the MTU to 1560 would solve the problem.
Have you tried applying this patch before testing it once again?
http://git.open-mesh.org/batman-adv.git/commit/746d6436f88899a79c1cb3b27af06...
Actually this patch is already part of the batman-adv package in openwrt. Therefore the question turns in: did you update the batman-adv package before performing your second test?
the second test was done today and yesterday's i updated bataman-adv.
Yes but we are creating confusion.
Maybe. Lets see.
In the second test you *enabled* network coding, therefore it is normal that the overhead grew up. This happens because NC uses more bytes for its header.
In both tests NC was enabled. I have NC enabled by default before and after the update. In fact is all tests NC is enabled by default and i undestand the increase to 1546 but to 1560 it surprised me. Should i still see the increase to 1560 or should it stayed at 1546 which would be 1532 ?
[Please don't remove the batman-adv mailing list from the CC field.]
unintentional mistake of too many buttons around :P
The first test you have performed was without the patch that fixes the value reported in that message.
Now that the patch is applied you have to see 1560 when NC is enabled and 1532 when it is disabled.
Doing some tests and with NC disabled:
uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
after reboot:
# dmesg | grep MTU [ 28.030000] batman_adv: bat0: The MTU of interface adhoc0 is too small (1546) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
uci show network | grep mtu network.mesh0.mtu=1546
changing the mtu to 1560 when NC is disabled:
# uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
# dmesg | grep MTU no output/result
# ifconfig | grep MTU UP BROADCAST RUNNING MULTICAST MTU:1560 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP LOOPBACK RUNNING MTU:16436 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Frist result if the adhoc interface with 1560
correct me if i am mistaken but according to you it should be 1532 ?
Changing it to 1532 still keeping network coding disabled.
uci set network.mesh0.mtu=1532 uci commit network reboot
uci show network| grep mtu network.mesh0.mtu=1532
uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
# dmesg | grep MTU [ 28.020000] batman_adv: bat0: The MTU of interface adhoc0 is too small (1532) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
# dmesg | grep MTU [ 28.020000] batman_adv: bat0: The MTU of interface adhoc0 is too small (1532) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
# ifconfig | grep MTU UP BROADCAST RUNNING MULTICAST MTU:1532 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP LOOPBACK RUNNING MTU:16436 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Changing now the MTU to 1560
uci set network.mesh0.mtu=1560 uci commit network reboot
Keeping batman-adv.bat0.network_coding=0
# uci show network| grep mtu network.mesh0.mtu=1560
# ifconfig | grep MTU UP BROADCAST RUNNING MULTICAST MTU:1560 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP LOOPBACK RUNNING MTU:16436 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
# dmesg | grep MTU no complaints.
if i enable network coding and the mtu to 1560 no complaints either.
Can you confirm?
confirmed ?
cheers,
On 22/01/14 01:52, cmsv wrote:
inline:
On 01/21/2014 07:31 PM, Antonio Quartulli wrote:
On 22/01/14 01:29, cmsv wrote:
On 01/21/2014 07:20 PM, Antonio Quartulli wrote:
On 22/01/14 01:14, cmsv wrote:
On 01/21/2014 07:06 PM, Antonio Quartulli wrote:
On 22/01/14 01:00, Antonio Quartulli wrote: > On 21/01/14 21:01, cmsv wrote: >> Yes i understand that but it keeps on increasing. >> [ 28.600000] batman_adv: bat0: The MTU of interface adhoc0 is too >> small (1546) to handle the transport of batman-adv packets. Packets >> going over this interface will be fragmented on layer2 which could >> impact the performance. Setting the MTU to 1560 would solve the problem. > > Have you tried applying this patch before testing it once again? > > http://git.open-mesh.org/batman-adv.git/commit/746d6436f88899a79c1cb3b27af06... >
Actually this patch is already part of the batman-adv package in openwrt. Therefore the question turns in: did you update the batman-adv package before performing your second test?
the second test was done today and yesterday's i updated bataman-adv.
Yes but we are creating confusion.
Maybe. Lets see.
In the second test you *enabled* network coding, therefore it is normal that the overhead grew up. This happens because NC uses more bytes for its header.
In both tests NC was enabled. I have NC enabled by default before and after the update. In fact is all tests NC is enabled by default and i undestand the increase to 1546 but to 1560 it surprised me. Should i still see the increase to 1560 or should it stayed at 1546 which would be 1532 ?
[Please don't remove the batman-adv mailing list from the CC field.]
unintentional mistake of too many buttons around :P
The first test you have performed was without the patch that fixes the value reported in that message.
Now that the patch is applied you have to see 1560 when NC is enabled and 1532 when it is disabled.
Doing some tests and with NC disabled:
uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
after reboot:
# dmesg | grep MTU [ 28.030000] batman_adv: bat0: The MTU of interface adhoc0 is too small (1546) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
uci show network | grep mtu network.mesh0.mtu=1546
changing the mtu to 1560 when NC is disabled:
# uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
# dmesg | grep MTU no output/result
# ifconfig | grep MTU UP BROADCAST RUNNING MULTICAST MTU:1560 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1440 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 UP LOOPBACK RUNNING MTU:16436 Metric:1 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Frist result if the adhoc interface with 1560
correct me if i am mistaken but according to you it should be 1532 ?
Changing it to 1532 still keeping network coding disabled.
uci set network.mesh0.mtu=1532 uci commit network reboot
uci show network| grep mtu network.mesh0.mtu=1532
uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
No, the MTU value changes only when NC is disabled at compile time.
Hi cmsv,
On 2014-01-22 01:52, cmsv wrote:
uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
after reboot:
# dmesg | grep MTU [ 28.030000] batman_adv: bat0: The MTU of interface adhoc0 is too small (1546) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
uci show network | grep mtu network.mesh0.mtu=1546
changing the mtu to 1560 when NC is disabled:
# uci show batman-adv | grep network_coding batman-adv.bat0.network_coding=0
# dmesg | grep MTU no output/result
It might not have been clear, but when we tell to disable NC, we are referring to the compile time options. batman-adv is not considering if NC is enabled/disabled at runtime when checking for MTU, but only checking if NC is compiled in or not.
It might make sense to check for runtime options when complaining about MTU in batman-adv, but I don't think so, as it complicates the checks whenever MTU is changed or NC is toggled.
// Martin
b.a.t.m.a.n@lists.open-mesh.org
-
Antonio Quartulli -
cmsv -
Martin Hundebøll