Hello,

I use same environment  for both tests, flashed board on SDCard, boot from SDCard and then mounted EMMC to execute iozone command

Florence

From: Remi Duraffort [mailto:remi.duraffort@linaro.org]
Sent: vendredi 26 janvier 2018 12:05
To: Neil Williams <neil.williams@linaro.org>
Cc: Florence ROUGER JUNG <florence.rouger-jung@st.com>; lava-users@lists.linaro.org
Subject: Re: [Lava-users] IOZone test to measure performance of DUT

Hello,

Are you running the board in the same environment for both tests?

For instance it might (I haven't tested) have some impacts if in one case you are booting using tftp/nfs and in second case booting from the emmc directly (flashed board).

2018-01-26 11:10 GMT+01:00 Neil Williams <neil.williams@linaro.org>:

On 26 January 2018 at 08:03, Florence ROUGER JUNG <florence.rouger-jung@st.com> wrote:

Hi All,

We use IOZone test to measure performance of our DUT 

Same command executed several time in a Lava session provide a diversity of results

iozone -az -i0 -i1 -I -e -s 100M -r 4k -r 16k -r 512k -r 1024k -r 16384k -f /mnt_emmc//tmp/iozone.tmp

Example1:

kB  reclen    write  rewrite    read    reread    read     write     read   rewrite      read   fwrite frewrite    fread  freread

102400       4     5053     4420    12471    12137

102400      16     5070     5218    22101    22207

102400     512    11733    12630    40799    40862

102400    1024    11446    11494    39982    39976

102400   16384    13839    14235    42093    42094

Example 2:

kB  reclen    write  rewrite    read    reread    read     write     read   rewrite      read   fwrite frewrite    fread  freread

102400       4     5088     5006    13496    13095

102400      16     5395     5549    17199    17220

102400     512     9203    10038    27819    27586

102400    1024     9382     8482    32514    32430

102400   16384    13569    13986    41992    42081

When same command is executed without LAVA with same DUT, results are more homogeneous  (similar to exemple1) and permit to define clear targets

I'm not familiar with IOZone, so any problem with those numbers needs to be fully explained - I can't see a pattern.

The command line suggests that you're expecting the data to be written directly to the DUT filesystem from a command running on the DUT, so LAVA is doing absolutely nothing during that operation.

How to reduce interaction from Lava to measure performance of DUT ?

During the execution of a Lava Test Shell there is no impact on the DUT from running it in LAVA - LAVA is simply watching for patterns on the serial connection and writing logs. LAVA is not interacting with the board in any way. During the operation of a test shell script, LAVA is in strictly read-only mode. Nothing is sent to the DUT once the test shell starts.

Is it possible to disable some checks / interactions with DUT during execution of each test (around 3 / 4 minutes) ?

Right now, that question doesn't make sense because there are no checks / interactions with the DUT during the execution of a test.

--

Neil Williams
=============
neil.williams@linaro.org
http://www.linux.codehelp.co.uk/

_______________________________________________
Lava-users mailing list
Lava-users@lists.linaro.org
https://lists.linaro.org/mailman/listinfo/lava-users

--

Rémi Duraffort

LAVA Team