From: Stephen Hemminger <stephen@networkplumber.org>
To: Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>
Cc: Fuji Nafiul <nafiul.fuji@gmail.com>, users@dpdk.org
Subject: Re: how to make dpdk processes tolerable to segmantation fault?
Date: Thu, 30 Nov 2023 13:19:46 -0800 [thread overview]
Message-ID: <20231130131946.428a070b@hermes.local> (raw)
In-Reply-To: <20231130192401.2e3f3c4c@sovereign>
On Thu, 30 Nov 2023 19:24:01 +0300
Dmitry Kozlyuk <dmitry.kozliuk@gmail.com> wrote:
> 2023-11-30 13:45 (UTC+0600), Fuji Nafiul:
> > In a normal c program, I saw that the segmentation fault in 1 loosely
> > coupled thread doesn't necessarily affect other threads or the main
> > program. There, I can check all the threads by process ID of it in every
> > certain period of time and if some unexepected segmentation fault occurs or
> > got killed I can re run the thread and it works fine. I can later monitor
> > the logs and inspect the situation.
> >
> > But I saw that, segmentation fault or other unexpected error in remotely
> > launched (using DPDK) functions on different core affects the whole dpdk
> > process and whole dpdk program crashes.. why is that?
> >
> > Is there any alternative way to handle this scenario ? How can I take
> > measures for unexpected future error occurance where I should auto rerun
> > dpdk remote processes in live system?
>
> Please consider running the buggy code that causes SIGSEGV
> in a separate process rather than a thread.
> If it must use DPDK, can it be made an independent app?
>
> DPDK is unlikely to ever support the described scenario.
> Continuing to run the process after SIGSEGV is inherently unsafe.
> Specifically, DPDK communicates with its lcore threads
> using pipes allocated at startup.
> If such thread crashed and a SIGSEGV not killing the app was installed,
> the communication would hang.
> Generally, DPDK employs user-space synchronization primitives,
> which cannot recover if one of the threads using them crashes.
A couple of things you can do.
- run your DPDK application as a systemd service which will be restarted
when you crash.
- catch SIGSEGV in the application an print a backtrace, then abort.
prev parent reply other threads:[~2023-11-30 21:19 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-30 7:45 Fuji Nafiul
2023-11-30 16:24 ` Dmitry Kozlyuk
2023-11-30 21:19 ` Stephen Hemminger [this message]
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=20231130131946.428a070b@hermes.local \
--to=stephen@networkplumber.org \
--cc=dmitry.kozliuk@gmail.com \
--cc=nafiul.fuji@gmail.com \
--cc=users@dpdk.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).