Data Acquisition and processing on Orange Pi Zero

[Nbird]

Hi,

 

I receive 16 bytes every 0.5 seconds. This should be saved as text or as MySQL table data.

 

Need to compare with all existing records , process and display it on 3.5 inch TFT LCD on SPI ( Notro fbtft ) and also save to SD Card . It should be broadcasted to a fixed Ip using TCPIP.

 

Can I use Orange Pi Zero with 512MB Ram ?

 

Can I partition Ram as RAMFS OR TMPFS to do all read only tasks thus save time for slow SD CARD writes ?

 

Can I first copy boot files and my app,tables to Ram and start from Ram ?

 

Any suggestions ?

 

Thanks

[Nbird]

Sorry, forgot to add that 16 bytes received from a UART

[Ney]

Hi, Orange Pi Zero could be a good choise.

I don't know what are the process exactly but may be Redis (all in RAM) with nodejs can do the job.

Redis save the database periodically on disk.

 

- https://redis.io/

- https://www.npmjs.com/package/ioredis

[SomeArmbianForumUser]

Need to compare with all existing records

 

This looks like a bottleneck. Define "all".

 

16 bytes every half second will fill up 512 MB RAM in a approx. half a year. Not taking into account overhead, compression, other processes that use RAM.

 

You should plan for a maximum measurement duration significantly lower than that. And check the performance of your DAQ system for the end of the planned measurement period, i.e. with a large set of simulated data already in memory.

[Nbird]

Hi Newbie,

 

Thanks for your suggestion.

 

Idea is to save the AQ logs to SD card of Pi-Zero.

 

Part of RAM is planned to be used as RAMFS where the application resides and gets executed from there. ( say 128MB) . This may be needed to minimise the SDIO read/write and give max time to SD ONLY to save AQ logs.

 

The Balance RAM ( 512-128) = 384MB be used as Program area.

 

The questions are:

 

a. Can the Kernel and application be transferred to RAMFS on first boot ?

b. If yes or No, what can be transferred to RAMFS to give minimum load to SDIO ( SD card) to avoid any crashes due to excessive resources usage.

 

 

Is there any other way that can be thought of ?

 

Thanks

Nbird

[SomeArmbianForumUser]

 

a. Can the Kernel and application be transferred to RAMFS on first boot ?

What's the point? Once started, they are in RAM anyway.

[Igor]

a and b are already optimised to more or less full degree, we have 10 minutes fs commit time by default - fstab: commit=600. Further put logs to tmpfs - ram, we used to have this by default too, but since we upgraded to systemd, we would need to rewrite scripting ...