Re: 2.4.0 Networking oddity
Daniel Walton wrote: > > The server in question is running the tulip driver. dmesg reports: > > Linux Tulip driver version 0.9.13 (January 2, 2001) > > I have seen this same behavior on a couple of my servers running 3com > 3c905c adaptors as well. > > The last time I was experiencing it I rebooted the system and it didn't > solve the problem. When it came up it was still lagging. This would lead > me to believe that it is caused by some sort of network condition, but what > I don't know. > > If anyone has ideas, I'd be more than happy to run tests/provide more info.. > If you are running an intelligent switch, double check to make sure your duplex and speed match what the switch sees on it's port. The biggest problem I've had with any of my machines is autonegotiation of port speed and duplex. Typically all that is required is that I force speed and duplex on the Linux end. Jordan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: 2.4.0 Networking oddity
Daniel Walton wrote: The server in question is running the tulip driver. dmesg reports: Linux Tulip driver version 0.9.13 (January 2, 2001) I have seen this same behavior on a couple of my servers running 3com 3c905c adaptors as well. The last time I was experiencing it I rebooted the system and it didn't solve the problem. When it came up it was still lagging. This would lead me to believe that it is caused by some sort of network condition, but what I don't know. If anyone has ideas, I'd be more than happy to run tests/provide more info.. If you are running an intelligent switch, double check to make sure your duplex and speed match what the switch sees on it's port. The biggest problem I've had with any of my machines is autonegotiation of port speed and duplex. Typically all that is required is that I force speed and duplex on the Linux end. Jordan - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: 2.4.0 Networking oddity
The server in question is running the tulip driver. dmesg reports: Linux Tulip driver version 0.9.13 (January 2, 2001) I have seen this same behavior on a couple of my servers running 3com 3c905c adaptors as well. The last time I was experiencing it I rebooted the system and it didn't solve the problem. When it came up it was still lagging. This would lead me to believe that it is caused by some sort of network condition, but what I don't know. If anyone has ideas, I'd be more than happy to run tests/provide more info.. -Dan At 10:14 PM 1/28/2001 -0500, you wrote: >In mailing-lists.linux-kernel, you wrote: > > >I am running a web server under the new 2.4.0 kernel and am experiencing > >some intermittent odd behavior from the kernel. The machine will sometimes > >go through cycles where network response becomes slow even though top > >reports over 60% idle CPU time. When this is happening ping goes from > >reasonable response times to response times of several seconds in cycles of > >about 15 to 20 seconds. > >FWIW, I have seen behaviour like this under kernel 2.2.x and 2.4.x, >for me taking the interface down and then bringing it back up usually >makes the problem stop, at least for the moment. > >I have always assumed that it is caused by a bug in the Ethernet card >driver, as the first time I noticed this behaviour, I was using the >Realtek 8139 driver about two years ago, it was really not good >hardware and the driver was pretty new. Anyway, it would do this, so >I contacted Donald Becker about it, he pointed me to a newer version >of the driver that did it _much_ less often. > >Cheers, >Wayne - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: 2.4.0 Networking oddity
In mailing-lists.linux-kernel, you wrote: >I am running a web server under the new 2.4.0 kernel and am experiencing >some intermittent odd behavior from the kernel. The machine will sometimes >go through cycles where network response becomes slow even though top >reports over 60% idle CPU time. When this is happening ping goes from >reasonable response times to response times of several seconds in cycles of >about 15 to 20 seconds. FWIW, I have seen behaviour like this under kernel 2.2.x and 2.4.x, for me taking the interface down and then bringing it back up usually makes the problem stop, at least for the moment. I have always assumed that it is caused by a bug in the Ethernet card driver, as the first time I noticed this behaviour, I was using the Realtek 8139 driver about two years ago, it was really not good hardware and the driver was pretty new. Anyway, it would do this, so I contacted Donald Becker about it, he pointed me to a newer version of the driver that did it _much_ less often. Cheers, Wayne - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
2.4.0 Networking oddity
I am running a web server under the new 2.4.0 kernel and am experiencing some intermittent odd behavior from the kernel. The machine will sometimes go through cycles where network response becomes slow even though top reports over 60% idle CPU time. When this is happening ping goes from reasonable response times to response times of several seconds in cycles of about 15 to 20 seconds. As a test I pinged another machine on the same network segment and received the same results listed above. On the other hand, I pinged from the other machine on the LAN to the problem machine and the ping times were a consistent 0.1ms. This tells me two things. One, that the network switch was not causing the problem, and two, that the problem is very likely somewhere in the handoff of packets from kernel-land to user-land on the problem server. Here is the ping results from the problem server to another machine on the same segment: 77 packets transmitted, 77 packets received, 0% packet loss round-trip min/avg/max = 0.2/4368.1/15126.6 ms Here are the ping results from the other machine to the problem server taken at exactly the same time: 116 packets transmitted, 115 packets received, 0% packet loss round-trip min/avg/max = 0.1/0.1/0.3 ms A little information about what I'm running. The server is running about 700Kbps continuous network output from nearly a thousand concurrent connections. The web server is a single process which utilizes the select/poll method of multiplexing. The machine is an 1gig Athlon processor with 512megs with RedHat 6.2 installed. I have the following tweaks setup in my rc.local file: echo "7168 32767 65535" > /proc/sys/net/ipv4/tcp_mem echo 32768 > /proc/sys/net/ipv4/tcp_max_orphans echo 4096 > /proc/sys/net/ipv4/tcp_max_syn_backlog echo 1 > /proc/sys/net/ipv4/tcp_syncookies echo 30 > /proc/sys/net/ipv4/tcp_fin_timeout echo 4 > /proc/sys/net/ipv4/tcp_syn_retries echo 7 > /proc/sys/net/ipv4/tcp_retries2 echo 300 > /proc/sys/net/ipv4/tcp_keepalive_time echo 30 > /proc/sys/net/ipv4/tcp_keepalive_intvl echo 16384 > /proc/sys/fs/file-max echo 16384 > /proc/sys/kernel/rtsig-max Am I simply missing something in my tweaks or is this a bug? I would be happy to supply more information if it would help anyone in the know on a problem like this. I appreciate any light anyone can shed on this subject. I've been trying to find the source of this problem for some time now. Daniel Walton - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
2.4.0 Networking oddity
I am running a web server under the new 2.4.0 kernel and am experiencing some intermittent odd behavior from the kernel. The machine will sometimes go through cycles where network response becomes slow even though top reports over 60% idle CPU time. When this is happening ping goes from reasonable response times to response times of several seconds in cycles of about 15 to 20 seconds. As a test I pinged another machine on the same network segment and received the same results listed above. On the other hand, I pinged from the other machine on the LAN to the problem machine and the ping times were a consistent 0.1ms. This tells me two things. One, that the network switch was not causing the problem, and two, that the problem is very likely somewhere in the handoff of packets from kernel-land to user-land on the problem server. Here is the ping results from the problem server to another machine on the same segment: 77 packets transmitted, 77 packets received, 0% packet loss round-trip min/avg/max = 0.2/4368.1/15126.6 ms Here are the ping results from the other machine to the problem server taken at exactly the same time: 116 packets transmitted, 115 packets received, 0% packet loss round-trip min/avg/max = 0.1/0.1/0.3 ms A little information about what I'm running. The server is running about 700Kbps continuous network output from nearly a thousand concurrent connections. The web server is a single process which utilizes the select/poll method of multiplexing. The machine is an 1gig Athlon processor with 512megs with RedHat 6.2 installed. I have the following tweaks setup in my rc.local file: echo "7168 32767 65535" /proc/sys/net/ipv4/tcp_mem echo 32768 /proc/sys/net/ipv4/tcp_max_orphans echo 4096 /proc/sys/net/ipv4/tcp_max_syn_backlog echo 1 /proc/sys/net/ipv4/tcp_syncookies echo 30 /proc/sys/net/ipv4/tcp_fin_timeout echo 4 /proc/sys/net/ipv4/tcp_syn_retries echo 7 /proc/sys/net/ipv4/tcp_retries2 echo 300 /proc/sys/net/ipv4/tcp_keepalive_time echo 30 /proc/sys/net/ipv4/tcp_keepalive_intvl echo 16384 /proc/sys/fs/file-max echo 16384 /proc/sys/kernel/rtsig-max Am I simply missing something in my tweaks or is this a bug? I would be happy to supply more information if it would help anyone in the know on a problem like this. I appreciate any light anyone can shed on this subject. I've been trying to find the source of this problem for some time now. Daniel Walton - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: 2.4.0 Networking oddity
In mailing-lists.linux-kernel, you wrote: I am running a web server under the new 2.4.0 kernel and am experiencing some intermittent odd behavior from the kernel. The machine will sometimes go through cycles where network response becomes slow even though top reports over 60% idle CPU time. When this is happening ping goes from reasonable response times to response times of several seconds in cycles of about 15 to 20 seconds. FWIW, I have seen behaviour like this under kernel 2.2.x and 2.4.x, for me taking the interface down and then bringing it back up usually makes the problem stop, at least for the moment. I have always assumed that it is caused by a bug in the Ethernet card driver, as the first time I noticed this behaviour, I was using the Realtek 8139 driver about two years ago, it was really not good hardware and the driver was pretty new. Anyway, it would do this, so I contacted Donald Becker about it, he pointed me to a newer version of the driver that did it _much_ less often. Cheers, Wayne - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
Re: 2.4.0 Networking oddity
The server in question is running the tulip driver. dmesg reports: Linux Tulip driver version 0.9.13 (January 2, 2001) I have seen this same behavior on a couple of my servers running 3com 3c905c adaptors as well. The last time I was experiencing it I rebooted the system and it didn't solve the problem. When it came up it was still lagging. This would lead me to believe that it is caused by some sort of network condition, but what I don't know. If anyone has ideas, I'd be more than happy to run tests/provide more info.. -Dan At 10:14 PM 1/28/2001 -0500, you wrote: In mailing-lists.linux-kernel, you wrote: I am running a web server under the new 2.4.0 kernel and am experiencing some intermittent odd behavior from the kernel. The machine will sometimes go through cycles where network response becomes slow even though top reports over 60% idle CPU time. When this is happening ping goes from reasonable response times to response times of several seconds in cycles of about 15 to 20 seconds. FWIW, I have seen behaviour like this under kernel 2.2.x and 2.4.x, for me taking the interface down and then bringing it back up usually makes the problem stop, at least for the moment. I have always assumed that it is caused by a bug in the Ethernet card driver, as the first time I noticed this behaviour, I was using the Realtek 8139 driver about two years ago, it was really not good hardware and the driver was pretty new. Anyway, it would do this, so I contacted Donald Becker about it, he pointed me to a newer version of the driver that did it _much_ less often. Cheers, Wayne - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/
