Re: cups slow on linux-2.6.24

[Patrick McHardy <kaber@trash.net>]

Jeff Chua wrote:
> On Jan 31, 2008 10:41 AM, Patrick McHardy <kaber@trash.net> wrote:
>
>   
>> Thanks. In the dump we can see that connections reusing ports
>> always have their first SYN dropped and retransmissted three
>> seconds later. I'm not sure whats causing this yet, do you have
>> any firewall rules that affect loopback traffic?
>>     
>
> No firewall.
>
> And the "lp" is just to print to a file@localhost.
>
> # lpadmin -p lp -i /etc/cups/interfaces/lp -v lpd://localhost/file -o
> printer-error-policy=retry-job
> # lpadmin -p file -i /etc/cups/interfaces/file -v file:/dev/null -o
> printer-error-policy=retry-job
>
> Filter for lp is ..
>   cat $6
>
> Filter for file is ...
>   cat $6 >/tmp/$$
>   

Actually its probably the SYN/ACK that is dropped. Please try whether

modprobe ipt_LOG
echo 255 >/proc/sys/net/netfilter/nf_conntrack_log_invalid

and then running the test again logs something to the ring buffer.
You don't need to run the entire test, just until you get a log
message from conntrack.