[cups.bugs] cups slow on linux-2.6.24

Patrick McHardy kaber at trash.net
Wed Jan 30 19:26:34 PST 2008

Jeff Chua wrote:
> On Jan 31, 2008 10:41 AM, Patrick McHardy <kaber at 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 at 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.

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