From: "Toke Høiland-Jørgensen" <toke@toke.dk>
To: Adrian Popescu <adriannnpopescu@gmail.com>
Cc: cake@lists.bufferbloat.net
Subject: Re: [Cake] Cake3 - source code and some questions
Date: Thu, 23 Apr 2015 13:01:03 +0200 [thread overview]
Message-ID: <87lhhj85xs.fsf@toke.dk> (raw)
In-Reply-To: <CAF3M4P21knWNJ0rez2W8ZNZcufL=_K+JnYeBxndPsE+NBD+g-w@mail.gmail.com> (Adrian Popescu's message of "Thu, 23 Apr 2015 13:56:42 +0300")
Adrian Popescu <adriannnpopescu@gmail.com> writes:
> Thanks to your experiment and your statement regarding CPU load on
> your box during testing, I was able to fix the problem.
Cool!
> It looks like this problem was being caused by power saving. Something
> changed between the older kernels and the newer ones. Changing the
> power saving settings in the BIOS brings back latency below 0.5
> milliseconds.
So is this the PCI bus power saving settings, or the CPU, or?
> This might have an impact some benchmarks which don't load up all CPU
> cores or which don't need a lot of CPU power. This is certainly
> something to keep an eye on when doing any kind of testing involving
> really low latencies or network schedulers.
Yes, definitely. Having things be worse during idle is definitely not
optimal. I wonder if there's a kernel-level setting that can affect this?
-Toke
next prev parent reply other threads:[~2015-04-23 11:01 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-12 9:39 Adrian Popescu
2015-04-12 9:58 ` Jonathan Morton
2015-04-12 10:24 ` Jonathan Morton
2015-04-12 12:33 ` Adrian Popescu
2015-04-12 18:57 ` Jonathan Morton
2015-04-16 12:14 ` Adrian Popescu
2015-04-16 13:25 ` Jonathan Morton
2015-04-16 13:48 ` Adrian Popescu
2015-04-16 19:26 ` Dave Taht
2015-04-22 21:02 ` Adrian Popescu
2015-04-23 0:45 ` Stephen Hemminger
2015-04-23 9:01 ` Toke Høiland-Jørgensen
2015-04-23 10:56 ` Adrian Popescu
2015-04-23 11:01 ` Toke Høiland-Jørgensen [this message]
2015-04-23 11:05 ` Adrian Popescu
2015-04-23 11:09 ` Toke Høiland-Jørgensen
2015-04-23 11:13 ` Jonathan Morton
2015-04-16 13:49 ` Sebastian Moeller
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