Mirror of the lttng-dev mailing list
 help / color / mirror / Atom feed
From: wolfgang.rostek@gmx.de (Wolfgang Rostek)
Subject: [lttng-dev] major variations in perfomance figures
Date: Fri, 3 Apr 2015 17:34:44 +0200	[thread overview]
Message-ID: <trinity-a202c764-638a-4c9a-b09f-c588cfe2cdb8-1428075284708@3capp-gmx-bs13> (raw)
In-Reply-To: <CA+jJMxuOT-zRW4k74C-gD3n4XP3mWO4HGYCLu=LT+EnMuRncAQ@mail.gmail.com>

...
> > Frequence scaling I can't imagine on my dektop machine.
> > It is a jump between 350ns and 800ns. In the loop below
> > all the events of one test run are of equal time distance,
> > either slow or fast.
> 
> Frequency scaling can still definitely play a role, even on a desktop machine.
> Also, Core i5 chips support Turbo Boost which should be disabled to
> perform benchmarks.
> 
> I'm guessing you get your time measurements from the timestamps in the
> trace?
Yes

I'm not hunting for a detailed benchmark. Only such a large variance makes
me thoughtful. For such a test I did expect some 10-30% but not this more 
than 200%.

Wolfgang R.



  reply	other threads:[~2015-04-03 15:34 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <trinity-1e9921b3-666b-4656-bcb8-a2125944698f-1427831168919@3capp-gmx-bs39>
2015-04-03 14:22 ` Jérémie Galarneau
2015-04-03 14:47   ` Wolfgang Rostek
2015-04-03 15:21     ` Jérémie Galarneau
2015-04-03 15:34       ` Wolfgang Rostek [this message]
2015-04-03 16:49 Jesper Derehag

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=trinity-a202c764-638a-4c9a-b09f-c588cfe2cdb8-1428075284708@3capp-gmx-bs13 \
    --to=wolfgang.rostek@gmx.de \
    /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