From: "Mário Kuka" <kuka@cesnet.cz>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: dev@dpdk.org, mdr@ashroe.eu, reshma.pattan@intel.com
Subject: Re: [PATCH v2 2/2] pcapng: check if writev() returns a partial write
Date: Mon, 1 Aug 2022 10:42:03 +0200 [thread overview]
Message-ID: <fc1c8052-c9e0-a952-c1e3-5838665c66dc@cesnet.cz> (raw)
In-Reply-To: <20220729111434.09f6845b@hermes.local>
[-- Attachment #1: Type: text/plain, Size: 1767 bytes --]
> As pcapng is used in the dpdk application it writes to a file.
> You could repurpose it to something else, but even a pipe will not
> give partial writes unless you configure the pipe as non-blocking.
>
> Writing to a non-blocking pipe is going to have a load of other problems.
>
> This seems like a purely hypothetical case, can't see why it needs to be addressed.
OK, I'm sending patch v3 which only fixes the IVO_MAX limit issue.
I've removed the changes related to the partial write check.
On 29/07/2022 20:14, Stephen Hemminger wrote:
> On Fri, 29 Jul 2022 19:08:41 +0200
> Mário Kuka <kuka@cesnet.cz> wrote:
>
>>> Since this is being written to a file, handling partial writes makes little
>>> sense. The only case where partial write would happen would be if filesystem
>>> was full. Retrying just adds unnecessary complexity.
>>>
>>> If you really want to track this, then add a dropped counter.
>> But the file descriptor doesn't have to refer to just a regular file, what
>> if it's a socket or a pipe or some device? The pcapng documentation doesn't
>> say anything about any restrictions, so the implementation should be fully
>> generic. What's the point of a function to write packets to a file
>> descriptor
>> where there's a risk that it won't write all the packets or that the
>> file will
>> by corrupted due to a partial write and still not even let me know about
>> it?
> As pcapng is used in the dpdk application it writes to a file.
> You could repurpose it to something else, but even a pipe will not
> give partial writes unless you configure the pipe as non-blocking.
>
> Writing to a non-blocking pipe is going to have a load of other problems.
>
> This seems like a purely hypothetical case, can't see why it needs to be addressed.
[-- Attachment #2: S/MIME Cryptographic Signature --]
[-- Type: application/pkcs7-signature, Size: 4299 bytes --]
next prev parent reply other threads:[~2022-08-01 8:42 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-25 15:28 [PATCH] pcapng: fix write more packets than IOV_MAX limit Mário Kuka
2022-07-25 15:57 ` Stephen Hemminger
2022-07-25 16:10 ` Stephen Hemminger
2022-07-29 7:18 ` [PATCH v2 0/2] pcapng: fix some issues with writing packets Mário Kuka
2022-07-29 7:18 ` [PATCH v2 1/2] pcapng: fix write more packets than IOV_MAX limit Mário Kuka
2022-07-29 7:18 ` [PATCH v2 2/2] pcapng: check if writev() returns a partial write Mário Kuka
2022-07-29 16:00 ` Stephen Hemminger
2022-07-29 17:08 ` Mário Kuka
2022-07-29 18:14 ` Stephen Hemminger
2022-08-01 8:42 ` Mário Kuka [this message]
2022-07-29 15:58 ` [PATCH v2 0/2] pcapng: fix some issues with writing packets Stephen Hemminger
2022-07-29 17:33 ` Mário Kuka
2022-08-01 8:40 ` [PATCH v3] pcapng: fix write more packets than IOV_MAX limit Mário Kuka
2022-08-01 15:33 ` Stephen Hemminger
2022-10-10 0:40 ` Thomas Monjalon
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=fc1c8052-c9e0-a952-c1e3-5838665c66dc@cesnet.cz \
--to=kuka@cesnet.cz \
--cc=dev@dpdk.org \
--cc=mdr@ashroe.eu \
--cc=reshma.pattan@intel.com \
--cc=stephen@networkplumber.org \
/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).