Re: [chrony-dev] SW/HW timestamping on Linux
I tested with that earlier. Almost all the timestamps were rejected. But I was using poll 0. I’ll have to test again with a longer polling interval. Denny > On Nov 22, 2016, at 07:43, Miroslav Lichvar wrote: > > Can you confirm that with the patch I sent you earlier > which waits with poll()?
Re: [chrony-dev] SW/HW timestamping on Linux
Perfect. Thank you. Denny > On Nov 22, 2016, at 07:34, Miroslav Lichvar wrote: > > I've pushed to the git an implementation of the idea I proposed > earlier, which assumes symmetric position of UDP data in received and > transmitted packets. You can modify the calculation or hardcode the RX > correction in process_hw_timestamp() in ntp_io_linux.c. It's the > rx_correction variable.
Re: [chrony-dev] SW/HW timestamping on Linux
On Mon, Nov 21, 2016 at 08:53:51PM -0800, Denny Page wrote: > I would not have expected this, and I haven’t dug into it, but looking at the > time to generate timestamps for pcap, I am seeing times of more than a > second(!). I am wondering what happens if we get to the point of sending the > next request before we have received the transmit timestamp for the prior > one. Given the speed of the units I’m testing with, it appears to be possible > to have received the second response before the first transmit timestamp. Are you saying it takes more than a second to receive the TX timestamp? Can you confirm that with the patch I sent you earlier which waits with poll()? An occasional long delay seems to be a common problem reported with some HW. When a TX timestamp of a packet is received after a new packet was already sent, the timestamp will be ignored. > Have you tested against a fast server with "minpoll 0 max poll 0”? I did, but maybe my server is not fast enough. -- Miroslav Lichvar -- To unsubscribe email chrony-dev-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-dev-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
Re: [chrony-dev] SW/HW timestamping on Linux
On Mon, Nov 21, 2016 at 09:29:13PM -0800, Denny Page wrote: > Just to make sure I test correctly, would you mind creating a diff for a test > version for me? One that a can plug a hard coded number of nanoseconds > correction for just packet receive? I've pushed to the git an implementation of the idea I proposed earlier, which assumes symmetric position of UDP data in received and transmitted packets. You can modify the calculation or hardcode the RX correction in process_hw_timestamp() in ntp_io_linux.c. It's the rx_correction variable. -- Miroslav Lichvar -- To unsubscribe email chrony-dev-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-dev-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
[chrony-dev] [GIT] chrony/chrony.git branch master updated. 2.4.1-113-gc7e7787
This is an automated email from git. It was generated because a ref change was pushed to the "chrony/chrony.git" repository. The branch, master has been updated via c7e778757abe4eff3be32ab8a49497b67c45d67b (commit) via c45be946ce12a95cff0ef3313e7726c7c37003ad (commit) via 258bcc21b8356f1d7b529442d39c71bbb2fe872b (commit) via db286ca6ead28d59d9ae3f41afa5946b16ed2b30 (commit) via 85fbfd9b150e899bde793c8a679798cfb1120985 (commit) via b819c7fe552bb2e12aa90d417400740ee010530c (commit) via 2b5c86b9a3e044f0cb1a1d231f7dc8b4ae7f242b (commit) via 0a848e2528aaef0b3347de0b49ce50da8dc1c9a4 (commit) via b443ec5ea585ecc6e9b1c644d8e32400e96f7eba (commit) via 37d1467368e63e65823465aa5eedaa76aba3bece (commit) via 1d9d19d76ba7952a86b8266e2cfdced114fca883 (commit) via 9603f0552a8d78ddd71e643e2a0c3361074bcb27 (commit) via 12befc2afd43b41c72e982e6b24966965697fcf1 (commit) via 78f20f7b3e3c424319a02f12f8d5fc16c90d0932 (commit) from 875b0e262c6b472766081b1ab9cc0ecabd460305 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log - commit c7e778757abe4eff3be32ab8a49497b67c45d67b Author: Miroslav Lichvar Date: Mon Nov 21 16:23:57 2016 +0100 ntp: transpose HW RX timestamps We need to transpose HW RX timestamps as HW timestamps are normally preamble timestamps and RX timestamps in NTP are supposed to be trailer timestamps. Without raw sockets we don't know the length of the packet at layer 2, so we make an assumption that UDP data start at the same position as in the last transmitted packet which had a HW TX timestamp. commit c45be946ce12a95cff0ef3313e7726c7c37003ad Merge: 258bcc2 db286ca Author: Miroslav Lichvar Date: Tue Nov 22 16:06:05 2016 +0100 Merge branch '2.4-stable' into HEAD commit 258bcc21b8356f1d7b529442d39c71bbb2fe872b Author: Miroslav Lichvar Date: Mon Nov 21 11:20:57 2016 +0100 refclock: don't compare sample time with samples from previous poll This is an improvement of commit 8f85291d23560508e03938bfa894294f73ad2d9e. --- Summary of changes: NEWS | 10 + ntp_io_linux.c | 128 + refclock.c | 10 - 3 files changed, 129 insertions(+), 19 deletions(-) hooks/post-receive -- chrony/chrony.git -- To unsubscribe email chrony-dev-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-dev-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
