From: Jan Blunck <jblunck@infradead.org>
To: Olivier Matz <olivier.matz@6wind.com>
Cc: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
"dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [RFC 0/8] mbuf: structure reorganization
Date: Thu, 16 Feb 2017 18:26:39 +0100 [thread overview]
Message-ID: <CALe+Z00Y_=4rsAjTeyaEzKFqtuMb6HMRUEUDL2LveJx6bWL-dA@mail.gmail.com> (raw)
In-Reply-To: <20170216144807.7add2c71@platinum>
On Thu, Feb 16, 2017 at 2:48 PM, Olivier Matz <olivier.matz@6wind.com> wrote:
> On Mon, 6 Feb 2017 18:41:27 +0000, "Ananyev, Konstantin"
> <konstantin.ananyev@intel.com> wrote:
>> >
>> > The main changes are:
>> > - reorder structure to increase vector performance on some non-ia
>> > platforms.
>> > - add a 64bits timestamp field in the 1st cache line
>>
>> Wonder why it deserves to be in first cache line?
>> How it differs from seqn below (pure SW stuff right now).
>
> In case the timestamp is set from a NIC value, it is set in the Rx
> path. So that's why I think it deserve to be located in the 1st cache
> line.
>
> As you said, the seqn is a pure sw stuff right: it is set in a lib, not
> in a PMD rx path.
>
If we talk about setting the timestamp value in the RX path this
implicitly means software timestamps. Hardware timestamping usually
works by letting the hardware inject sync events for coarse time
tracking and additionally injecting fine granular per-packet ticks at
a specific offset in the packet. Out of performance reasons I don't
think it makes sense to extract this during the burst and write it
into the mbuf again.
The problem with timestamps is to get the abstraction right wrt the
correction factors and the size of the tick vs. the timestamp in the
events injected. From my perspective it would be better to extract the
handling of timestamp data into a library with PMD specific
implementation of the conversions. That way the normalized timestamp
values can get extracted if they are present. The mbuf itself would
only indicate the presence of timestamp metadata in that case.
next prev parent reply other threads:[~2017-02-16 17:26 UTC|newest]
Thread overview: 155+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-24 15:19 Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 1/8] mbuf: make segment prefree function public Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 2/8] mbuf: make raw free " Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 3/8] mbuf: set mbuf fields while in pool Olivier Matz
2017-01-24 15:50 ` Bruce Richardson
2017-02-28 14:51 ` Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 4/8] net: don't touch mbuf next or nb segs on Rx Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 5/8] mbuf: make rearm data address naturally aligned Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 6/8] mbuf: use 2 bytes for port and nb segments Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 7/8] mbuf: move sequence number in second cache line Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 8/8] mbuf: add a timestamp field Olivier Matz
2017-01-24 15:59 ` [dpdk-dev] [RFC 0/8] mbuf: structure reorganization Bruce Richardson
2017-01-24 16:16 ` Olivier MATZ
2017-02-06 18:41 ` Ananyev, Konstantin
2017-02-09 16:20 ` Morten Brørup
2017-02-09 16:56 ` Ananyev, Konstantin
2017-02-16 13:48 ` Olivier Matz
2017-02-16 15:46 ` Bruce Richardson
2017-02-16 16:14 ` Olivier Matz
2017-02-21 14:20 ` Morten Brørup
2017-02-21 14:28 ` Bruce Richardson
2017-02-21 15:04 ` Olivier MATZ
2017-02-21 15:18 ` Bruce Richardson
2017-02-21 15:18 ` Morten Brørup
2017-02-19 19:04 ` Chilikin, Andrey
2017-02-21 9:53 ` Olivier MATZ
2017-02-16 17:26 ` Jan Blunck [this message]
2017-02-17 10:51 ` Olivier Matz
2017-02-17 12:49 ` Nélio Laranjeiro
2017-02-17 13:51 ` Jan Blunck
2017-02-18 5:48 ` Andrew Rybchenko
2017-02-17 13:38 ` Jan Blunck
2017-02-17 14:17 ` Olivier Matz
2017-02-17 18:42 ` Ananyev, Konstantin
2017-02-21 9:53 ` Olivier MATZ
2017-02-21 10:28 ` Ananyev, Konstantin
2017-02-20 9:27 ` Jan Blunck
2017-02-21 9:54 ` Olivier MATZ
2017-02-21 16:12 ` Jan Blunck
2017-02-21 16:38 ` Bruce Richardson
2017-02-21 17:04 ` Jan Blunck
2017-02-21 17:26 ` Ananyev, Konstantin
2017-02-21 19:17 ` Jan Blunck
2017-02-21 20:30 ` Ananyev, Konstantin
2017-02-21 21:51 ` Morten Brørup
2017-02-24 14:11 ` Olivier Matz
2017-02-24 14:00 ` Olivier Matz
2017-02-24 14:21 ` Bruce Richardson
2017-02-28 8:55 ` Jan Blunck
2017-02-28 9:05 ` Ananyev, Konstantin
2017-02-28 9:23 ` Olivier Matz
2017-02-28 9:33 ` Jan Blunck
2017-02-28 10:29 ` Ananyev, Konstantin
2017-02-28 10:50 ` Olivier Matz
2017-02-28 11:48 ` Ananyev, Konstantin
2017-02-28 12:28 ` Olivier Matz
2017-02-28 22:53 ` Ananyev, Konstantin
2017-03-02 16:46 ` Olivier Matz
2017-03-08 11:11 ` Ananyev, Konstantin
2017-03-20 9:00 ` Olivier Matz
2017-03-22 17:42 ` Ananyev, Konstantin
2017-03-24 8:35 ` Jerin Jacob
2017-03-24 13:35 ` Olivier Matz
2017-02-28 9:25 ` Jan Blunck
2017-02-19 23:45 ` Ananyev, Konstantin
2017-02-21 9:22 ` Morten Brørup
2017-02-21 9:54 ` Olivier MATZ
2017-03-08 9:41 ` [dpdk-dev] [PATCH 0/9] " Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 1/9] mbuf: make segment prefree function public Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 2/9] mbuf: make raw free " Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 3/9] mbuf: set mbuf fields while in pool Olivier Matz
2017-03-31 11:21 ` Bruce Richardson
2017-03-31 11:51 ` Ananyev, Konstantin
2017-03-08 9:41 ` [dpdk-dev] [PATCH 4/9] drivers/net: don't touch mbuf next or nb segs on Rx Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 5/9] mbuf: make rearm data address naturally aligned Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 6/9] mbuf: use 2 bytes for port and nb segments Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 7/9] mbuf: move sequence number in second cache line Olivier Matz
2017-03-08 9:42 ` [dpdk-dev] [PATCH 8/9] mbuf: add a timestamp field Olivier Matz
2017-04-04 10:29 ` [dpdk-dev] [PATCH 0/2] reduce writes to mbuf in ixgbe vRX Konstantin Ananyev
2017-04-07 15:13 ` Ferruh Yigit
2017-04-07 15:44 ` Ferruh Yigit
2017-04-09 22:56 ` Ananyev, Konstantin
2017-04-04 10:29 ` [dpdk-dev] [PATCH 1/2] net/ixgbe: eliminate mbuf write on rearm Konstantin Ananyev
2017-04-10 15:59 ` [dpdk-dev] [PATCH v2 0/2] reduce writes to mbuf in ixgbe vRX Konstantin Ananyev
2017-04-10 16:17 ` Ferruh Yigit
2017-04-10 15:59 ` [dpdk-dev] [PATCH v2 1/2] net/ixgbe: eliminate mbuf write on rearm Konstantin Ananyev
2017-04-10 15:59 ` [dpdk-dev] [PATCH v2 2/2] net/ixgbe: remove option to disable offload flags Konstantin Ananyev
2017-04-04 10:29 ` [dpdk-dev] [PATCH " Konstantin Ananyev
2017-03-08 9:42 ` [dpdk-dev] [PATCH 9/9] mbuf: reorder VLAN tci and buffer len fields Olivier Matz
2017-03-29 15:56 ` [dpdk-dev] [PATCH 0/9] mbuf: structure reorganization Olivier Matz
2017-03-29 16:03 ` Morten Brørup
2017-03-29 20:09 ` Bruce Richardson
2017-03-30 9:31 ` Bruce Richardson
2017-03-30 12:02 ` Olivier Matz
2017-03-30 12:23 ` Bruce Richardson
2017-03-30 16:45 ` Ananyev, Konstantin
2017-03-30 16:47 ` Ananyev, Konstantin
2017-03-30 18:06 ` Ananyev, Konstantin
2017-03-31 8:41 ` Olivier Matz
2017-03-31 9:58 ` Ananyev, Konstantin
2017-03-31 1:00 ` Ananyev, Konstantin
2017-03-31 7:21 ` Morten Brørup
2017-03-31 8:26 ` Olivier Matz
2017-03-31 8:41 ` Bruce Richardson
2017-03-31 8:59 ` Olivier Matz
2017-03-31 9:18 ` Ananyev, Konstantin
2017-03-31 9:36 ` Olivier Matz
2017-04-03 16:15 ` Thomas Monjalon
2017-04-04 7:58 ` Olivier MATZ
2017-04-04 8:53 ` Bruce Richardson
2017-03-31 9:23 ` Bruce Richardson
2017-03-31 11:18 ` Nélio Laranjeiro
2017-03-30 14:54 ` Andrew Rybchenko
2017-03-30 15:12 ` Jerin Jacob
2017-04-04 16:27 ` [dpdk-dev] [PATCH v2 0/8] " Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 1/8] mbuf: make segment prefree function public Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 2/8] mbuf: make raw free " Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 3/8] mbuf: set mbuf fields while in pool Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 4/8] drivers/net: don't touch mbuf next or nb segs on Rx Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 5/8] mbuf: make rearm data address naturally aligned Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nb segments Olivier Matz
2017-04-06 5:45 ` Yuanhan Liu
2017-04-18 13:03 ` Olivier MATZ
2017-07-04 7:54 ` Wang, Zhihong
2017-07-10 8:00 ` Olivier Matz
2017-07-10 8:15 ` Morten Brørup
2017-07-11 13:25 ` Wiles, Keith
2017-07-11 13:30 ` Morten Brørup
2017-07-11 15:05 ` Thomas Monjalon
2017-07-11 15:23 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nbsegments Morten Brørup
2017-07-11 16:48 ` Wiles, Keith
2017-07-12 7:25 ` Morten Brørup
2017-07-12 9:02 ` Yang, Zhiyong
2017-07-12 9:50 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port andnbsegments Morten Brørup
2017-07-12 15:35 ` Stephen Hemminger
2017-07-12 15:57 ` Morten Brørup
2017-07-12 16:23 ` Thomas Monjalon
2017-07-12 18:20 ` Wiles, Keith
2017-07-21 15:03 ` Bruce Richardson
2017-07-12 15:34 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nbsegments Wiles, Keith
2017-07-11 13:34 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nb segments Wiles, Keith
2017-07-11 13:46 ` Olivier MATZ
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 7/8] mbuf: move sequence number in second cache line Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 8/8] mbuf: add a timestamp field Olivier Matz
2017-04-05 9:37 ` [dpdk-dev] [PATCH v2 0/8] mbuf: structure reorganization Thomas Monjalon
2017-04-05 9:46 ` Olivier MATZ
2017-04-05 9:48 ` Richardson, Bruce
2017-04-05 12:06 ` Ferruh Yigit
2017-04-14 13:10 ` Ferruh Yigit
2017-04-18 13:04 ` Olivier MATZ
2017-04-19 9:39 ` Thomas Monjalon
2017-04-19 12:28 ` Olivier MATZ
2017-04-19 12:56 ` Thomas Monjalon
2017-04-19 13:03 ` Ferruh Yigit
2017-04-19 13:12 ` Thomas Monjalon
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