From: "Mattias Rönnblom" <mattias.ronnblom@ericsson.com>
To: "Morten Brørup" <mb@smartsharesystems.com>,
"Thomas Monjalon" <thomas@monjalon.net>,
"Van Haaren Harry" <harry.van.haaren@intel.com>
Cc: David Marchand <david.marchand@redhat.com>,
dpdklab <dpdklab@iol.unh.edu>, "ci@dpdk.org" <ci@dpdk.org>,
Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>,
Aaron Conole <aconole@redhat.com>, dev <dev@dpdk.org>
Subject: Re: rte_service unit test failing randomly
Date: Thu, 6 Oct 2022 08:59:07 +0000 [thread overview]
Message-ID: <aef2561c-ee84-f4ba-632e-a0f3d5642dd3@ericsson.com> (raw)
In-Reply-To: <98CBD80474FA8B44BF855DF32C47DC35D8739B@smartserver.smartshare.dk>
On 2022-10-06 10:18, Morten Brørup wrote:
>> From: Mattias Rönnblom [mailto:mattias.ronnblom@ericsson.com]
>> Sent: Thursday, 6 October 2022 09.51
>>
>> On 2022-10-06 08:53, Morten Brørup wrote:
>
> [...]
>
>>> I have been wondering how accurate the tests really are. Where can I
>> see what is being done to ensure that the EAL worker threads are fully
>> isolated, and never interrupted by the O/S scheduler or similar?
>>>
>>
>> There are kernel-level counters for how many times a thread have been
>> involuntarily interrupted,
>
> Thanks, Mattias. I will look into that.
>
> Old kernels (2.4 and 2.6) ascribed the time spent in interrupt handlers to the CPU usage of the running process, instead of counting the time spent in interrupt handlers separately. Does anyone know it this has been fixed?
>
If you mean top half interrupt handler, my guess would be it does not
matter, except in some strange corner cases or faulty hardware. An ISR
should have very short run time, and not being run *that* often (after
NAPI). With isolated cores, it should be even less of a problem, but
then you may not have that.
Bottom halves are not attributed to the process, I believe. (In old
kernels, the time spent in soft IRQs were not attributed to anything,
which could create situations where the system was very busy indeed
[e.g., with network stack bottom halves doing IP forwarding], but
looking idle in 'top'.)
>> and also, if I recall correctly, the amount
>> of wall-time the thread have been runnable, but not running (i.e.,
>> waiting to be scheduled). The latter may require some scheduler debug
>> kernel option being enabled on the kernel build.
>
>
next prev parent reply other threads:[~2022-10-06 8:59 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-05 19:14 David Marchand
2022-10-05 20:33 ` Mattias Rönnblom
2022-10-05 20:52 ` Thomas Monjalon
2022-10-05 21:33 ` Mattias Rönnblom
2022-10-06 6:53 ` Morten Brørup
2022-10-06 7:04 ` David Marchand
2022-10-06 7:50 ` Morten Brørup
2022-10-06 7:50 ` Mattias Rönnblom
2022-10-06 8:18 ` Morten Brørup
2022-10-06 8:59 ` Mattias Rönnblom [this message]
2022-10-06 9:49 ` Morten Brørup
2022-10-06 11:07 ` [dpdklab] " Lincoln Lavoie
2022-10-06 12:00 ` Morten Brørup
2022-10-06 17:52 ` Honnappa Nagarahalli
2022-10-06 13:51 ` Aaron Conole
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=aef2561c-ee84-f4ba-632e-a0f3d5642dd3@ericsson.com \
--to=mattias.ronnblom@ericsson.com \
--cc=Honnappa.Nagarahalli@arm.com \
--cc=aconole@redhat.com \
--cc=ci@dpdk.org \
--cc=david.marchand@redhat.com \
--cc=dev@dpdk.org \
--cc=dpdklab@iol.unh.edu \
--cc=harry.van.haaren@intel.com \
--cc=mb@smartsharesystems.com \
--cc=thomas@monjalon.net \
/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).