Hi, I am stresstesting httpd (Apache 1.3.31) under native linux and xenolinux on order to evaluate the server performance in both environments. The hardware for each subsequent runs is identical, and I also tried to keep the software configuration as similar as possible (same versions of packages installed, same services enabled/disabled etc.) To test the performance of httpd I am using httperf with either persistend and non-persistent connections. When persistent connections are enebled, I get very close performance on xenolinux to native Linux, but when they are disabled the server performance over xenolinux really suffers. To give you a rough estimates how bad it is here are some numbers. persistent enabled reply rate native xenolinux 4000 req/sec 3900 rep/sec 700 rep/sec persistent disabled 4000 req/sec 3950 rep/sec 3950 rep/sec I understand why the case of persistent connections performs better than the non-persistent, however in the former case httpd performance under xenolinux is buffeling to me. I suspect it is due to misconfiguration rather than xen issue and I will appreciate if some of you provide any advices on what needs to be checked. The modifications that I have made to the kernel configuration of linux, dom0 and dom0 are the following # enable tcp time-wait recycling echo 1 > /proc/sys/net/ipv4/tcp_tw_recycle #disable tcp timestamps echo 0 > /proc/sys/net/ipv4/tcp_timestamps # increase the number of local ports that are available for use echo 5000 65535 > /proc/sys/net/ipv4/ip_local_port_range max number of open file descriptors for each processor is increased to 32K. Native linux runs FC2 2.8.1 kernel that was compiled with different configuration than 2.6.8.1-xen0 and 2.6.8.1-xenU. (perhaps the first place to check?) nayden ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
> etc.) To test the performance of httpd I am using httperf > with either persistend and non-persistent connections. When > persistent connections are enebled, I get very close > performance on xenolinux to native Linux, but when they are > disabled the server performance over xenolinux really > suffers. To give you a rough estimates how bad it is here > are some numbers.Have you enabled connection tracking in the dom0 kernel as this can slow things down? Does ''dmesg'' show anything being logged? [Just to be sure, are you getting the poor performance with non persistent connections, right?] Ian> persistent enabled reply rate native xenolinux > 4000 req/sec 3900 rep/sec 700 rep/sec > persistent disabled > 4000 req/sec 3950 rep/sec > 3950 rep/sec > > I understand why the case of persistent connections performs > better than the non-persistent, however in the former case > httpd performance under xenolinux is buffeling to me. > > I suspect it is due to misconfiguration rather than xen issue > and I will appreciate if some of you provide any advices on > what needs to be checked. > > The modifications that I have made to the kernel > configuration of linux, dom0 and dom0 are the following # > enable tcp time-wait recycling echo 1 > > /proc/sys/net/ipv4/tcp_tw_recycle > > #disable tcp timestamps > echo 0 > /proc/sys/net/ipv4/tcp_timestamps > > # increase the number of local ports that are available for > use echo 5000 65535 > /proc/sys/net/ipv4/ip_local_port_range > > max number of open file descriptors for each processor is > increased to 32K. > > Native linux runs FC2 2.8.1 kernel that was compiled with > different configuration than 2.6.8.1-xen0 and 2.6.8.1-xenU. > (perhaps the first place to check?) > > nayden > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide Read honest & > candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://productguide.itmanagersjournal.com/ > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xen-devel > >------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
I am getting the follwoing messages from dmesg in Dom1, which are rather suspicious. TCP: drop open request from 192.168.0.14/26284 printk: 8712 messages suppressed. TCP: drop open request from 192.168.0.14/36324 printk: 8921 messages suppressed. TCP: drop open request from 192.168.0.13/45416 192.168.0.13/14 are machines on which I am running httperf. Since I am getting similar messages on native linux this probmel is one thing that I am investigating. nayden On Sat, 4 Dec 2004 08:24:17 -0000, Ian Pratt <m+ian.pratt@cl.cam.ac.uk> wrote:> > etc.) To test the performance of httpd I am using httperf > > with either persistend and non-persistent connections. When > > persistent connections are enebled, I get very close > > performance on xenolinux to native Linux, but when they are > > disabled the server performance over xenolinux really > > suffers. To give you a rough estimates how bad it is here > > are some numbers. > > Have you enabled connection tracking in the dom0 kernel as this can slow > things down? Does ''dmesg'' show anything being logged? > > [Just to be sure, are you getting the poor performance with non > persistent connections, right?] > > Ian > > > > > persistent enabled reply rate native xenolinux > > 4000 req/sec 3900 rep/sec 700 rep/sec > > persistent disabled > > 4000 req/sec 3950 rep/sec > > 3950 rep/sec > > > > I understand why the case of persistent connections performs > > better than the non-persistent, however in the former case > > httpd performance under xenolinux is buffeling to me. > > > > I suspect it is due to misconfiguration rather than xen issue > > and I will appreciate if some of you provide any advices on > > what needs to be checked. > > > > The modifications that I have made to the kernel > > configuration of linux, dom0 and dom0 are the following # > > enable tcp time-wait recycling echo 1 > > > /proc/sys/net/ipv4/tcp_tw_recycle > > > > #disable tcp timestamps > > echo 0 > /proc/sys/net/ipv4/tcp_timestamps > > > > # increase the number of local ports that are available for > > use echo 5000 65535 > /proc/sys/net/ipv4/ip_local_port_range > > > > max number of open file descriptors for each processor is > > increased to 32K. > > > > Native linux runs FC2 2.8.1 kernel that was compiled with > > different configuration than 2.6.8.1-xen0 and 2.6.8.1-xenU. > > (perhaps the first place to check?) > > > > nayden > > > > > > ------------------------------------------------------- > > SF email is sponsored by - The IT Product Guide Read honest & > > candid reviews on hundreds of IT Products from real users. > > Discover which products truly live up to the hype. Start reading now. > > http://productguide.itmanagersjournal.com/ > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/xen-devel > > > > >------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel