Re: [PATCH 00/23] per device dirty throttling -v8

[david@lang.hm]

On Sat, 4 Aug 2007, Ray Lee wrote:

> On 8/4/07, david@lang.hm <david@lang.hm> wrote:
>> On Sat, 4 Aug 2007, Ingo Molnar wrote:
>>
> At least on a surface level, your report has some similarities to
> http://lkml.org/lkml/2007/5/21/84 . In that message, John Miller
> mentions several things he tried without effect:
>
> < - I increased the max allowed receive buffer through
> < proc/sys/net/core/rmem_max and the application calls the right
> < syscall. "netstat -su" does not show any "packet receive errors".

mercury1:/proc/sys/net/core# cat rmem_*
124928
131071
mercury1:/proc/sys/net/core# netstat -su
Udp:
     697853177 packets received
     10025642 packets to unknown port received.
     191726680 packet receive errors
     63194 packets sent
     RcvbufErrors: 191726680
UdpLite:
mercury1:/proc/sys/net/core# echo "512000" >rmem_max

> < - After getting "kernel: swapper: page allocation failure.
> < order:0, mode:0x20", I increased /proc/sys/vm/min_free_kbytes

I have not seen any similar errors

> < - ixgb.txt in kernel network documentation suggests to increase
> < net.core.netdev_max_backlog to 300000. This did not help.

mercury1:/proc/sys/net/core# cat netdev_*
300
1000
mercury1:/proc/sys/net/core# echo "300000" >netdev_max_backlog

> < - I also had to increase net.core.optmem_max, because the default
> < value was too small for 700 multicast groups.

I'm not running multicast.

> As they're all pretty simple to test, it may be worthwhile to give
> them a shot just to rule things out.

unfortunantly the load is not high enough right now to see a real 
difference (it's only doing ~1400 logs/sec) I'll catch it at a higher load 
point to see if these make any difference.

David Lang

> Ray
>