Re: [systemd-devel] network-online.target time
Am 22.04.20 um 16:44 schrieb Peter Morrow: > I'm trying to optimise our boot process and have started to look at > the time it takes for the network to come up (a single interface to be > routable) when using systemd-networkd: > > So, here systemd-networkd-wait-online.service seems to run for 3.5s - > I had initially though this is due to the RTT for DHCP but in doing a > packet capture for DHCP this isn't the case: > > Can anyone offer any suggestions for where I should look to try to > speed things up here? it *is* dhcp - it's that simple 10.587s network-up.service 9.116s network-wan-dhcp.service "network-wan-dhcp.service" in our case is simply started by "network-up.service" which is a simple selfmade unit using ip-commands and nothing else there is no way to make that simpler as in my setup [root@srv-rhsoft:~]$ systemctl status network-wan-dhcp.service ● network-wan-dhcp.service - Internet DHCP-Client Loaded: loaded (/etc/systemd/system/network-wan-dhcp.service; static; vendor preset: disabled) Active: active (running) since Tue 2020-04-21 19:24:58 CEST; 21h ago Main PID: 1296 (dhclient) Tasks: 1 (limit: 512) Memory: 4.6M CPU: 86ms CGroup: /system.slice/network-wan-dhcp.service └─1296 /usr/sbin/dhclient -4 -q --no-pid --request-options subnet-mask,routers br-wan ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] network-online.target time
On Wed, 2020-05-06 at 17:51 +0200, Lennart Poettering wrote: > On Mi, 06.05.20 15:50, Peter Morrow ( > peter.mor...@microsoft.com > ) wrote: > > > On Wed, 2020-05-06 at 17:39 +0200, Lennart Poettering wrote: > > > On Mi, 22.04.20 14:44, Peter Morrow ( > > > peter.mor...@microsoft.com > > > > > > ) wrote: > > > > > > > Hi Folks, > > > > > > > > I'm trying to optimise our boot process and have started to > > > > look at > > > > the time it takes for the network to come up (a single > > > > interface to > > > > be > > > > routable) when using systemd-networkd: > > > > > > > > Can anyone offer any suggestions for where I should look to try > > > > to > > > > speed things up here? > > > > > > Turn on debug logging for networkd. it should tell you what it is > > > doing, and the timestamps should allow you to determine what > > > precisely > > > is being waited for. > > > > Thanks. Yes - I ended up doing this and it turned out much of the > > additional time is down to ipv6 interface > > configuration. Specifically > > ipv6 link local duplicate address detection. > > You can turn that off if you like: IPv6DuplicateAddressDetection= This option worked well when I tried it (total time came down to ~700ms) but unfortunately disabling it entirely isn't an option. FWIW setting CONFIG_IPV6_OPTIMISTIC_DAD=y in the kernel is providing a good middle ground. Peter. > Lennart > > -- > Lennart Poettering, Berlin ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] network-online.target time
On Wed, 2020-05-06 at 17:39 +0200, Lennart Poettering wrote: > On Mi, 22.04.20 14:44, Peter Morrow ( > peter.mor...@microsoft.com > ) wrote: > > > Hi Folks, > > > > I'm trying to optimise our boot process and have started to look at > > the time it takes for the network to come up (a single interface to > > be > > routable) when using systemd-networkd: > > > > Can anyone offer any suggestions for where I should look to try to > > speed things up here? > > Turn on debug logging for networkd. it should tell you what it is > doing, and the timestamps should allow you to determine what > precisely > is being waited for. Thanks. Yes - I ended up doing this and it turned out much of the additional time is down to ipv6 interface configuration. Specifically ipv6 link local duplicate address detection. Peter. > > Lennart > > -- > Lennart Poettering, Berlin > ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] network-online.target time
On Mi, 06.05.20 15:50, Peter Morrow (peter.mor...@microsoft.com) wrote: > On Wed, 2020-05-06 at 17:39 +0200, Lennart Poettering wrote: > > On Mi, 22.04.20 14:44, Peter Morrow ( > > peter.mor...@microsoft.com > > ) wrote: > > > > > Hi Folks, > > > > > > I'm trying to optimise our boot process and have started to look at > > > the time it takes for the network to come up (a single interface to > > > be > > > routable) when using systemd-networkd: > > > > > > Can anyone offer any suggestions for where I should look to try to > > > speed things up here? > > > > Turn on debug logging for networkd. it should tell you what it is > > doing, and the timestamps should allow you to determine what > > precisely > > is being waited for. > > Thanks. Yes - I ended up doing this and it turned out much of the > additional time is down to ipv6 interface configuration. Specifically > ipv6 link local duplicate address detection. You can turn that off if you like: IPv6DuplicateAddressDetection= Lennart -- Lennart Poettering, Berlin ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
Re: [systemd-devel] network-online.target time
On Mi, 22.04.20 14:44, Peter Morrow (peter.mor...@microsoft.com) wrote: > Hi Folks, > > I'm trying to optimise our boot process and have started to look at > the time it takes for the network to come up (a single interface to be > routable) when using systemd-networkd: > > Can anyone offer any suggestions for where I should look to try to > speed things up here? Turn on debug logging for networkd. it should tell you what it is doing, and the timestamps should allow you to determine what precisely is being waited for. Lennart -- Lennart Poettering, Berlin ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
[systemd-devel] network-online.target time
Hi Folks, I'm trying to optimise our boot process and have started to look at the time it takes for the network to come up (a single interface to be routable) when using systemd-networkd: root@HOST:/# systemd-analyze critical-chain network-online.target --no- pager The time after the unit is active or started is printed after the "@" character. The time the unit takes to start is printed after the "+" character. network-online.target @4.144s └─systemd-networkd-wait-online.service @615ms +3.527s └─systemd-networkd.service @582ms +30ms └─systemd-tmpfiles-setup.service @315ms +63ms └─local-fs.target @314ms root@HOST:/# So, here systemd-networkd-wait-online.service seems to run for 3.5s - I had initially though this is due to the RTT for DHCP but in doing a packet capture for DHCP this isn't the case: me@DHCP-SERVER:~$ sudo tshark -i eth0 -f "(ether src 28:16:a8:fd:53:77 || ether dst 28:16:a8:fd:53:77) && (port 67 || port 68)" Running as user "root" and group "root". This could be dangerous. Capturing on 'eth0' 1 0.0 0.0.0.0 → 255.255.255.255 DHCP 333 DHCP Discover - Transaction ID 0x5c9e3cd0 2 0.000157300 192.168.3.3 → 192.168.3.16 DHCP 373 DHCP Offer- Transaction ID 0x5c9e3cd0 3 0.000695601 0.0.0.0 → 255.255.255.255 DHCP 345 DHCP Request - Transaction ID 0x5c9e3cd0 4 0.000771901 192.168.3.3 → 192.168.3.16 DHCP 373 DHCP ACK - Transaction ID 0x5c9e3cd0 So, that's 700us from discover to ack. We have 3 network interfaces, only enP8p1s0f0np0 is of use to us: root@HOST:/# networkctl status -a --no-pager ● 1: lo Link File: /usr/lib/systemd/network/99-default.link Network File: n/a Type: loopback State: carrier (unmanaged) Address: 127.0.0.1 ::1 ● 2: enP8p1s0f0np0 Link File: /usr/lib/systemd/network/99-default.link Network File: /etc/systemd/network/wired.network Type: ether State: routable (configured) Path: platform-6040.pcie-pci-0008:01:00.0 Driver: bnxt_en HW Address: 28:16:a8:fd:53:77 Address: 192.168.3.16 2001:db8:0:1:2a16:a8ff:fefd:5377 fe80::2a16:a8ff:fefd:5377 Gateway: 192.168.3.1 fe80::7683:efff:fed4:935 DNS: 10.50.10.50 10.50.50.50 NTP: 10.222.184.12 Connected To: localhost on port Ethernet31/1 ● 3: enP8p1s0f1np0 Link File: /usr/lib/systemd/network/99-default.link Network File: n/a Type: ether State: off (unmanaged) Path: platform-6040.pcie-pci-0008:01:00.1 Driver: bnxt_en HW Address: 00:10:18:ad:05:01 root@HOST:/# Networking configuration looks like this: root@HOST:/# cat /etc/systemd/network/wired.network [Match] Name=eth* en* [Network] DHCP=v4 root@HOST:/# cat /etc/systemd/network/ blacklist_interfaces.network wired.network root@HOST:/# cat /etc/systemd/network/blacklist_interfaces.network [Match] Name=enP8p1s0f1* [Network] DHCP=no LinkLocalAddressing=no IPv6AcceptRA=false [Link] RequiredForOnline=no Unmanaged=yes root@HOST:/# Our version is: root@HOST:/# systemctl --version systemd 239 +PAM +AUDIT +SELINUX +IMA -APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP -GCRYPT -GNUTLS -ACL +XZ -LZ4 -SECCOMP +BLKID -ELFUTILS +KMOD -IDN2 -IDN -PCRE2 default-hierarchy=unified root@HOST:/# I've had a look at https://github.com/systemd/systemd/blob/v239/src/network/wait-online/wait-online.c and it really doesn't do much other than wait for the operational state to be "routable". Can anyone offer any suggestions for where I should look to try to speed things up here? Thanks! Peter. ___ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
