DPDK patches and discussions
 help / color / mirror / Atom feed
From: Maxime Coquelin <maxime.coquelin@redhat.com>
To: Zhihong Wang <zhihong.wang@intel.com>, dev@dpdk.org
Cc: yuanhan.liu@linux.intel.com, thomas.monjalon@6wind.com
Subject: Re: [dpdk-dev] [PATCH v5 0/6] vhost: optimize enqueue
Date: Mon, 12 Sep 2016 15:56:43 +0200	[thread overview]
Message-ID: <6177acfd-c97b-fb72-0c94-d71377a00aaf@redhat.com> (raw)
In-Reply-To: <3a40c167-c21e-8cb6-33ae-6043cb13b463@redhat.com>



On 09/12/2016 03:52 PM, Maxime Coquelin wrote:
> Hi,
>
> On 09/09/2016 05:39 AM, Zhihong Wang wrote:
>> This patch set optimizes the vhost enqueue function.
>>
>> It implements the vhost logic from scratch into a single function
>> designed
>> for high performance and good maintainability, and improves CPU
>> efficiency
>> significantly by optimizing cache access, which means:
>>
>>  *  Higher maximum throughput can be achieved for fast frontends like
>> DPDK
>>     virtio pmd.
>>
>>  *  Better scalability can be achieved that each vhost core can support
>>     more connections because it takes less cycles to handle each single
>>     frontend.
>>
>> This patch set contains:
>>
>>  1. A Windows VM compatibility fix for vhost enqueue in 16.07 release.
>>
>>  2. A baseline patch to rewrite the vhost logic.
>>
>>  3. A series of optimization patches added upon the baseline.
>>
>> The main optimization techniques are:
>>
>>  1. Reorder code to reduce CPU pipeline stall cycles.
>>
>>  2. Batch update the used ring for better efficiency.
>>
>>  3. Prefetch descriptor to hide cache latency.
>>
>>  4. Remove useless volatile attribute to allow compiler optimization.
>>
>> Code reordering and batch used ring update bring most of the performance
>> improvements.
>>
>> In the existing code there're 2 callbacks for vhost enqueue:
>>
>>  *  virtio_dev_merge_rx for mrg_rxbuf turned on cases.
>>
>>  *  virtio_dev_rx for mrg_rxbuf turned off cases.
>>
>> The performance of the existing code is not optimal, especially when the
>> mrg_rxbuf feature turned on. Besides, having 2 callback paths increases
>> maintenance efforts.
>>
>> Also, there's a compatibility issue in the existing code which causes
>> Windows VM to hang when the mrg_rxbuf feature turned on.
>>
>> ---
>> Changes in v5:
>>
>>  1. Rebase to the latest branch.
>>
>>  2. Rename variables to keep consistent in naming style.
>>
>>  3. Small changes like return value adjustment and vertical alignment.
>>
>>  4. Add details in commit log.
> Just tried to apply your series without success.
> Apparently, it is not based directly on master branch,
> as it lacks some SHA-1 information.
>
> Could you rebase it against master please?

Ok, it is in fact based on top of:
git://dpdk.org/next/dpdk-next-virtio master

For v6, if any, could you add this info to the cover letter please?

Thanks,
Maxime

  reply	other threads:[~2016-09-12 13:56 UTC|newest]

Thread overview: 140+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-16  3:50 [dpdk-dev] [PATCH] optimize vhost enqueue Zhihong Wang
2016-08-16 13:59 ` Maxime Coquelin
2016-08-17  1:45   ` Wang, Zhihong
2016-08-17  2:38     ` Yuanhan Liu
2016-08-17  6:41       ` Wang, Zhihong
2016-08-17  9:17         ` Maxime Coquelin
2016-08-17  9:51           ` Yuanhan Liu
2016-08-18 13:44             ` Wang, Zhihong
2016-08-17 10:07           ` Wang, Zhihong
2016-08-18  6:33 ` [dpdk-dev] [PATCH v2 0/6] vhost: optimize enqueue Zhihong Wang
2016-08-18  6:33   ` [dpdk-dev] [PATCH v2 1/6] vhost: rewrite enqueue Zhihong Wang
2016-08-19  2:39     ` Yuanhan Liu
2016-08-19  7:07       ` Wang, Zhihong
2016-08-18  6:33   ` [dpdk-dev] [PATCH v2 2/6] vhost: remove obsolete Zhihong Wang
2016-08-19  2:32     ` Yuanhan Liu
2016-08-19  7:08       ` Wang, Zhihong
2016-08-18  6:33   ` [dpdk-dev] [PATCH v2 3/6] vhost: remove useless volatile Zhihong Wang
2016-08-18  6:33   ` [dpdk-dev] [PATCH v2 4/6] vhost: add desc prefetch Zhihong Wang
2016-08-18  6:33   ` [dpdk-dev] [PATCH v2 5/6] vhost: batch update used ring Zhihong Wang
2016-08-18  6:33   ` [dpdk-dev] [PATCH v2 6/6] vhost: optimize cache access Zhihong Wang
2016-08-19  5:43 ` [dpdk-dev] [PATCH v3 0/5] vhost: optimize enqueue Zhihong Wang
2016-08-19  5:43   ` [dpdk-dev] [PATCH v3 1/5] vhost: rewrite enqueue Zhihong Wang
2016-08-22  9:35     ` Maxime Coquelin
2016-08-23  2:27       ` Wang, Zhihong
2016-08-25  4:00       ` Yuanhan Liu
2016-08-19  5:43   ` [dpdk-dev] [PATCH v3 2/5] vhost: remove useless volatile Zhihong Wang
2016-08-19  5:43   ` [dpdk-dev] [PATCH v3 3/5] vhost: add desc prefetch Zhihong Wang
2016-08-19  5:43   ` [dpdk-dev] [PATCH v3 4/5] vhost: batch update used ring Zhihong Wang
2016-08-25  3:48     ` Yuanhan Liu
2016-08-25  5:19       ` Wang, Zhihong
2016-08-19  5:43   ` [dpdk-dev] [PATCH v3 5/5] vhost: optimize cache access Zhihong Wang
2016-08-22  8:11   ` [dpdk-dev] [PATCH v3 0/5] vhost: optimize enqueue Maxime Coquelin
2016-08-22 10:01     ` Maxime Coquelin
2016-08-22 10:35       ` Thomas Monjalon
2016-08-24  3:37         ` Wang, Zhihong
2016-08-23  2:31       ` Wang, Zhihong
2016-08-23 10:43         ` Wang, Zhihong
2016-08-23 12:16           ` Maxime Coquelin
2016-08-23 12:22           ` Yuanhan Liu
2016-08-23  2:15     ` Wang, Zhihong
2016-09-21  8:50     ` Jianbo Liu
2016-09-21  9:27       ` Wang, Zhihong
2016-09-21 12:54         ` Jianbo Liu
2016-09-22  2:11           ` Wang, Zhihong
2016-09-22  2:29           ` Yuanhan Liu
2016-09-22  5:47             ` Jianbo Liu
2016-09-22  6:58               ` Wang, Zhihong
2016-09-22  9:01                 ` Jianbo Liu
2016-09-22 10:04                   ` Wang, Zhihong
2016-09-22 14:41                     ` Jianbo Liu
2016-09-23  2:56                       ` Wang, Zhihong
2016-09-23 10:41                         ` Jianbo Liu
2016-09-23 13:41                           ` Thomas Monjalon
2016-09-25  5:41                             ` Wang, Zhihong
2016-09-26  5:12                               ` Jianbo Liu
2016-09-26  5:25                                 ` Wang, Zhihong
2016-09-26  5:38                                   ` Jianbo Liu
2016-09-26  6:00                                     ` Wang, Zhihong
2016-09-26  4:24                             ` Jianbo Liu
2016-09-26  5:37                   ` Luke Gorrie
2016-09-26  5:40                     ` Jianbo Liu
2016-09-27 10:21                   ` Yuanhan Liu
2016-09-27 16:45                     ` Wang, Zhihong
2016-10-09 12:09                       ` Wang, Zhihong
2016-10-10  2:44                         ` Yuanhan Liu
2016-10-10  5:31                           ` Jianbo Liu
2016-10-10  6:22                             ` Wang, Zhihong
2016-10-10  6:57                               ` Jianbo Liu
2016-10-10  7:25                                 ` Wang, Zhihong
2016-10-12  2:53               ` Yuanhan Liu
2016-10-12 12:22                 ` Wang, Zhihong
2016-10-12 15:31                   ` Thomas Monjalon
2016-10-13  1:21                     ` Wang, Zhihong
2016-10-13  3:51                     ` Jianbo Liu
2016-10-13  5:33                   ` Yuanhan Liu
2016-10-13  5:35                     ` Yuanhan Liu
2016-10-13  6:02                     ` Wang, Zhihong
2016-10-13  7:54                       ` Maxime Coquelin
2016-10-13  9:23                         ` Maxime Coquelin
2016-10-14 10:11                           ` Yuanhan Liu
2016-08-30  3:35 ` [dpdk-dev] [PATCH v4 0/6] " Zhihong Wang
2016-08-30  3:35   ` [dpdk-dev] [PATCH v4 1/6] vhost: fix windows vm hang Zhihong Wang
2016-09-05  5:24     ` [dpdk-dev] [dpdk-stable] " Yuanhan Liu
2016-09-05  5:25       ` Wang, Zhihong
2016-09-05  5:40         ` Yuanhan Liu
2016-08-30  3:36   ` [dpdk-dev] [PATCH v4 2/6] vhost: rewrite enqueue Zhihong Wang
2016-09-05  6:39     ` Yuanhan Liu
2016-09-07  5:33       ` Yuanhan Liu
2016-09-07  5:39         ` Wang, Zhihong
2016-08-30  3:36   ` [dpdk-dev] [PATCH v4 3/6] vhost: remove useless volatile Zhihong Wang
2016-08-30  3:36   ` [dpdk-dev] [PATCH v4 4/6] vhost: add desc prefetch Zhihong Wang
2016-08-30  3:36   ` [dpdk-dev] [PATCH v4 5/6] vhost: batch update used ring Zhihong Wang
2016-08-30  3:36   ` [dpdk-dev] [PATCH v4 6/6] vhost: optimize cache access Zhihong Wang
2016-09-09  3:39 ` [dpdk-dev] [PATCH v5 0/6] vhost: optimize enqueue Zhihong Wang
2016-09-09  3:39   ` [dpdk-dev] [PATCH v5 1/6] vhost: fix windows vm hang Zhihong Wang
2016-09-09  3:39   ` [dpdk-dev] [PATCH v5 2/6] vhost: rewrite enqueue Zhihong Wang
2016-09-12 15:42     ` Maxime Coquelin
2016-09-14  8:20       ` Wang, Zhihong
2016-09-15 16:35         ` Maxime Coquelin
2016-09-12 16:26     ` Maxime Coquelin
2016-09-14  8:22       ` Wang, Zhihong
2016-09-18 14:19     ` Yuanhan Liu
2016-09-19  3:29       ` Wang, Zhihong
2016-09-09  3:39   ` [dpdk-dev] [PATCH v5 3/6] vhost: remove useless volatile Zhihong Wang
2016-09-09  3:39   ` [dpdk-dev] [PATCH v5 4/6] vhost: add desc prefetch Zhihong Wang
2016-09-09  3:39   ` [dpdk-dev] [PATCH v5 5/6] vhost: batch update used ring Zhihong Wang
2016-09-12 15:45     ` Maxime Coquelin
2016-09-14  8:43       ` Wang, Zhihong
2016-09-15 16:38         ` Maxime Coquelin
2016-09-18  2:55           ` Yuanhan Liu
2016-09-18  2:57             ` Wang, Zhihong
2016-09-09  3:39   ` [dpdk-dev] [PATCH v5 6/6] vhost: optimize cache access Zhihong Wang
2016-09-12 13:52   ` [dpdk-dev] [PATCH v5 0/6] vhost: optimize enqueue Maxime Coquelin
2016-09-12 13:56     ` Maxime Coquelin [this message]
2016-09-12 14:01     ` Yuanhan Liu
2016-09-20  2:00 ` [dpdk-dev] [PATCH v6 " Zhihong Wang
2016-09-20  2:00   ` [dpdk-dev] [PATCH v6 1/6] vhost: fix windows vm hang Zhihong Wang
2016-10-13  6:18     ` [dpdk-dev] [dpdk-stable] " Yuanhan Liu
2016-09-20  2:00   ` [dpdk-dev] [PATCH v6 2/6] vhost: rewrite enqueue Zhihong Wang
2016-09-22  9:58     ` Jianbo Liu
2016-09-22 10:13       ` Wang, Zhihong
2016-09-20  2:00   ` [dpdk-dev] [PATCH v6 3/6] vhost: remove useless volatile Zhihong Wang
2016-09-20  2:00   ` [dpdk-dev] [PATCH v6 4/6] vhost: add desc prefetch Zhihong Wang
2016-09-20  2:00   ` [dpdk-dev] [PATCH v6 5/6] vhost: batch update used ring Zhihong Wang
2016-09-20  2:00   ` [dpdk-dev] [PATCH v6 6/6] vhost: optimize cache access Zhihong Wang
2016-09-21  2:26   ` [dpdk-dev] [PATCH v6 0/6] vhost: optimize enqueue Yuanhan Liu
2016-09-21  4:39     ` Maxime Coquelin
2016-10-14  9:34   ` [dpdk-dev] [PATCH v7 0/7] vhost: optimize mergeable Rx path Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 1/7] vhost: remove useless volatile Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 2/7] vhost: optimize cache access Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 3/7] vhost: simplify mergeable Rx vring reservation Yuanhan Liu
2016-10-25 22:08       ` Thomas Monjalon
2016-10-26  2:56         ` Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 4/7] vhost: use last avail idx for avail ring reservation Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 5/7] vhost: shadow used ring update Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 6/7] vhost: prefetch avail ring Yuanhan Liu
2016-10-14  9:34     ` [dpdk-dev] [PATCH v7 7/7] vhost: retrieve avail head once Yuanhan Liu
2016-10-18  2:25     ` [dpdk-dev] [PATCH v7 0/7] vhost: optimize mergeable Rx path Jianbo Liu
2016-10-18 14:53     ` Maxime Coquelin
2016-10-21  7:51     ` Yuanhan Liu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6177acfd-c97b-fb72-0c94-d71377a00aaf@redhat.com \
    --to=maxime.coquelin@redhat.com \
    --cc=dev@dpdk.org \
    --cc=thomas.monjalon@6wind.com \
    --cc=yuanhan.liu@linux.intel.com \
    --cc=zhihong.wang@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).