Re: Expected behavior of Tomcat under load

2011-05-26 Thread Asankha Perera
Hi Peter / Chris My sincere apologies, as I somehow missed this original reply from Peter :( Operating system and version? Java version? ubuntu@ip-10-202-99-31:~/configs$ uname -a Linux ip-10-202-99-31 2.6.35-24-virtual #42-Ubuntu SMP Thu Dec 2 05:15:26 UTC 2010 x86_64 GNU/Linux

Re: Expected behavior of Tomcat under load

2011-05-26 Thread André Warnier
Something puzzles me since your first post : Asankha Perera wrote: ... No. TimeSourceDestination Protocol Src Port Dst Port Info 389961 37.056567 10.77.69.810.101.29.42 TCP 9062 8080 9062 8080 [SYN] Seq=0 Win=5792 [TCP

RE: Expected behavior of Tomcat under load

2011-05-26 Thread Caldarale, Charles R
From: André Warnier [mailto:a...@ice-sa.com] Subject: Re: Expected behavior of Tomcat under load What is this TCP CHECKSUM INCORRECT thing ? Usually because the checksum for outbound messages is being computed by the NIC rather than the TCP/IP stack software, so the protocol analyzer

Re: Expected behavior of Tomcat under load

2011-05-26 Thread Asankha C. Perera
Something puzzles me since your first post : ... What is this TCP CHECKSUM INCORRECT thing ? This is the output of some protocol analyser thing, right ? Yes, its a capture from tcpdump, analyzed by wireshark So it is totally independent of Tomcat or whatever. This packet is one that comes

RE: Expected behavior of Tomcat under load

2011-05-26 Thread Caldarale, Charles R
From: Asankha Perera [mailto:asankha.apa...@gmail.com] On Behalf Of Asankha C. Perera Subject: Re: Expected behavior of Tomcat under load Offload parameters for eth0: rx-checksumming: on tx-checksumming: on As expected, the NIC is handling the checksumming. - Chuck THIS COMMUNICATION

Re: Expected behavior of Tomcat under load

2011-05-26 Thread André Warnier
Putting your answer together with the one from Chuck : I understand that if the tcpdump program runs on the same host as the one which is sending the packets, it may not be able to correctly see the TCP checksum, since it captures the packet before it goes out on the network, and it is the NIC

Re: Expected behavior of Tomcat under load

2011-05-26 Thread Asankha C. Perera
On 05/26/2011 09:50 PM, André Warnier wrote: Putting your answer together with the one from Chuck : I understand that if the tcpdump program runs on the same host as the one which is sending the packets, it may not be able to correctly see the TCP checksum, since it captures the packet before

Re: Expected behavior of Tomcat under load

2011-05-26 Thread André Warnier
Asankha C. Perera wrote: On 05/26/2011 09:50 PM, André Warnier wrote: Putting your answer together with the one from Chuck : I understand that if the tcpdump program runs on the same host as the one which is sending the packets, it may not be able to correctly see the TCP checksum, since it

Expected behavior of Tomcat under load

2011-05-25 Thread Asankha C. Perera
Hi All During some performance tests, we've seen that Tomcat resets TCP connections under high load. To reproduce this rather consistently, a thread pool with a maximum of 300 threads could be configured on default Tomcat 6.0.32, and then 1280 ~ 2560 concurrent user requests simulated from a

Re: Expected behavior of Tomcat under load

2011-05-25 Thread Peter Crowther
Operating system and version? Java version? Tomcat version: 6.0.32 - thanks for this. Java or native connector? Pure Tomcat or something else in front? (I'm assuming pure Tomcat from what else you say) - Peter On 25 May 2011 12:51, Asankha C. Perera asan...@apache.org wrote: Hi All During