FreeBSD 7.1 tcp problem (syncache)?

[Petri Helenius]

I couldn't get Apache 2.2 ab to work on 7.0 at all. The ab from 2.0 
worked fine...

Pete


Andre Oppermann wrote:
> Paulo Fragoso wrote:
>> Hi,
>>
>> We was using one machine with FreeBSD 6.4-RELEASE running 
>> apache-worker-2.2.3 + mysql, this server can answer high request from 
>> one client using ab:
>>
>> {client}$ ab -n 2000 -c 1000 http://system_using_6.4-RELEASE
>> ...
>> Benchmarking ***** (be patient)
>> Completed 200 requests
>> Completed 400 requests
>> Completed 600 requests
>> Completed 800 requests
>> Completed 1000 requests
>> Completed 1200 requests
>> Completed 1400 requests
>> Completed 1600 requests
>> Completed 1800 requests
>> Finished 2000 requests
>> ...
>> {client}$
>>
>> Using other hardware whit FreeBSD 7.1-PRERELEASE running 
>> apache-worker-2.2.9_5 + mysql, we have a poor result:
>>
>> {client}$ ab -n 2000 -c 1000 http://system_using_7.1-PRERELEASE
>> ...
>> Test aborted after 10 failures
>>
>> apr_connect(): Invalid argument (22)
>> {client}$
>>
>> Looking for a problem on new server log we found:
>>
>> kernel: TCP: [client]:50197 to [server]:80 tcpflags 0x4<RST>; 
>> syncache_chkrst: Spurious RST without matching syncache entry 
>> (possibly syncookie only), segment ignored
>> kernel: TCP: [client]:53845 to [server]:80 tcpflags 0x4<RST>; 
>> syncache_chkrst: Spurious RST without matching syncache entry 
>> (possibly syncookie only), segment ignored
>> kernel: TCP: [client]:53845 to [server]:80 tcpflags 0x4<RST>; 
>> syncache_chkrst: Spurious RST without matching syncache entry 
>> (possibly syncookie only), segment ignored
>
> This error is harmless and occurs when the client closes the socket
> before the TCP session has terminated.  The RST have crossed and hit
> the syncache.  The same happens on 6.4 but it never told you about it.
>
>> All sysctl and apache conf are same on both server, is there a tcp 
>> problem with FreeBSD 7.x?
>
> Are you using the HTTP accept filter on the server?  This may cause
> the listen accept queue to overflow.
>
> Please post the output of "netstat -n -s -p tcp" to further diagnose
> the problem.
>