Logging Data download times

mstevens · September 2017

I see in the FAQ :

It will take about 30 seconds to download 1MB of log entries.

It will take abut 30 minutes to download 8MB of log entries.

1. Can you explain why this is?

2. What can I do to bring this time down. I'm using sensor fusion. How can I log at a lesser frequency using linear acceleration.

Thanks,
Mark

Eric · September 2017

Bluetooth LE does not transfer data that quickly compared to classic Bluetooth or WiFi.
Use the periodic sampling data processor

https://mbientlab.com/iosdocs/latest/data_processor.html#periodic-sampling

mstevens · September 2017

ok thanks,

I'm just confused why 1 mb takes 30 seconds while 8 mb takes 30 minutes.

Mark

Laura · September 2017

Mark,

The more data you have in the MetaSensor memory, the longer it will take to download via the Bluetooth link of your device. 8MB is a lot of data, that could be half a million sensor data entries!

Check out our amazing Bluetooth and memory tutorials here: https://mbientlab.com/tutorials/AboutBluetooth.html

Also we have a memory size calculator here: https://mbientlab.com/tutorials/Calculator.html

It should help clear things up!

mstevens · September 2017

I understand that it is more data but why does it take so much longer for 8mb, if 1 mb takes 30 seconds, shouldn't it only take 4 minutes for 8mb? I'm just wondering what the reason for this is.

Eric · October 2017

Ah yes, the time should scale linearly. Did a check with the MetaBase app and a 1MB download takes ~3min. FAQ has been corrected.

Logging Data download times

Comments