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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] cache lines, and 60000 cycles of doom
Date: Fri, 20 Jun 2014 07:50:40 -0400	[thread overview]
Message-ID: <1b3bfeff9117336767b881178d1f8b6a@brasstown.quanstro.net> (raw)
In-Reply-To: <CAFgOgC9oeGtBp3mA2QRLfsgeziTxYjhwMBvFGuQjoYiCAHCDBQ@mail.gmail.com>

On Fri Jun 20 01:04:20 EDT 2014, devon.odell@gmail.com wrote:

> Weird. I assume cycles is using rdtsc or rdtscp. Perhaps some of it is due
> to a combination of contention and rdtsc(p) being serializing instructions?
> On Jun 19, 2014 12:04 PM, "erik quanstrom" <quanstro@quanstro.net> wrote:

other than the code i posted, nobody else touching the Srb,
and it's bigger than a cacheline.

why would serialization cause a big issue?

- erik



  reply	other threads:[~2014-06-20 11:50 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-19 16:01 erik quanstrom
2014-06-20  5:03 ` Devon H. O'Dell
2014-06-20 11:50   ` erik quanstrom [this message]
2014-06-20 12:47     ` Devon H. O'Dell
2014-06-20 13:07       ` erik quanstrom
2014-06-20  5:09 ` Bakul Shah
2014-06-20 11:45   ` erik quanstrom

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