if mulitnode api don't privide the "parameter queue mechanism",how can realized multi client access simultaneously server resource?
For example, a test scene that have a server roler and two client roler. how dows roler server know message is from which client? Need user write a program to implement it(queue mechanism)? 
 roler server:
   steps:
    - lava-wait ipv4   
    - ipdata=$(cat /tmp/lava_multi_node_cache.txt | cut -d = -f 2) 
    ..
 roler client1:
   steps:
      - lava-send ipv4 ip=192
      .. 
 roler client2:
   steps:
      - lava-send ipv4 ip=193 
      ..
 from roler server , ipdata  can't be sured 192 or 193.



Steve McIntyre <steve.mcintyre@linaro.org> 于2019年5月13日周一 下午9:03写道:
Hi Jack,

On Mon, May 13, 2019 at 06:17:32PM +0800, jack lu wrote:
>The multinode function of "pass data between devices".Note:
>"The message data is stored in a cache file which will be overwritten when the
>next synchronisation call is made. Ensure that your scripts make use of (or
>copy aside) any MultiNode cache data before calling any other MultiNode API
>helpers that may clear the cache."
>
>Does it mean follow example:
>roler1:
>    ..
>   steps:
>      - lava-send ipv4 ip=192
>      - lava-send ipv4 ip=193
>      ..
>roler2:
>    step2:
>    - lava-wait ipv4   
>    - ipdata=$(cat /tmp/lava_multi_node_cache.txt | cut -d = -f 2)
>        ..
>After run, is content of roler2  ipdata 193?

It's likely, but there's no guarantee on that - you've given the jobs
no way to synchronise to be sure. Depending on timing between the two
test devices, you could get either 192 or 193.

Cheers,
--
Steve McIntyre                                steve.mcintyre@linaro.org
<http://www.linaro.org/> Linaro.org | Open source software for ARM SoCs