[dpdk-dev] [PATCH] doc: add limitations section to cryptoperf guide

Mrozowicz, SlawomirX slawomirx.mrozowicz at intel.com
Wed Feb 8 10:31:55 CET 2017



>-----Original Message-----
>From: Trahe, Fiona
>Sent: Tuesday, February 7, 2017 5:33 PM
>To: dev at dpdk.org
>Cc: De Lara Guarch, Pablo <pablo.de.lara.guarch at intel.com>; Mrozowicz,
>SlawomirX <slawomirx.mrozowicz at intel.com>; Jain, Deepak K
><deepak.k.jain at intel.com>; Trahe, Fiona <fiona.trahe at intel.com>; Griffin,
>John <john.griffin at intel.com>; Doherty, Declan <declan.doherty at intel.com>
>Subject: [PATCH] doc: add limitations section to cryptoperf guide
>
>Add limitations to use of the dpdk-test-crypto-perf tool for hardware
>accelerator measurements
>
>Signed-off-by: Fiona Trahe <fiona.trahe at intel.com>
>---
> doc/guides/tools/cryptoperf.rst |   16 ++++++++++++++++
> 1 files changed, 16 insertions(+), 0 deletions(-)
>
>diff --git a/doc/guides/tools/cryptoperf.rst b/doc/guides/tools/cryptoperf.rst
>index 6832312..af58e78 100644
>--- a/doc/guides/tools/cryptoperf.rst
>+++ b/doc/guides/tools/cryptoperf.rst
>@@ -41,6 +41,22 @@ chain mode have to be specified in the command line as
>application  parameters. These parameters are checked using device
>capabilities  structure.
>
>+Limitations:
>+------------
>+On hardware devices the cycle-count doesn't always represent the actual
>+offload cost. The cycle-count only represents the offload cost when the
>+hardware accelerator is not fully loaded, when loaded the cpu cycles
>+freed up by the offload are still consumed by the test tool and included in
>the cycle-count.
>+These cycles are consumed by retries and inefficient API calls
>+enqueuing and dequeuing smaller bursts than specified by the cmdline
>+parameter. This results in a larger cycle-count measurement and should
>+not be interpreted as an offload cost measurement.
>+
>+On hardware devices the throughput measurement is not necessarily the
>+maximum possible for the device, e.g. it may be necessary to use
>+multiple cores to keep the hardware accelerator fully loaded and so measure
>maximum throughput.
>+
>+
> Compiling the Application
> -------------------------
>
>--
>1.7.0.7

>From my point of view this information is ok.
Sławomir



More information about the dev mailing list