Local Server File Usage and Storage

HISTORY: Built local blynk server on Raspberry Pi3 w/ 16G SD. Have 5 different apps sending data packages frequently (yes I like fast updates :-). Recently I noticed by Supercharts did not have historical data (like 6 hours or 1 day ago). After research realized that I was out of storage. And unfortunately my first thought was re-boot - wrong - had to build new linux environment and LONG process. However out of this experience I decided I needed to relocate storage - so I started examining files and I am curious as to what they all are - and why some are stored every day.

FILES: So my understanding of a few of them (mm-dd are month and day)

  1. Blynk.Log 2019-mm-dd: Appears to have everything I do/send (I am in TRACE mode - so i believe this is why it is 500M per day)
  2. Stats.log.2019.mm.dd: Not totally certain looks like widgets and counts matrix - but why daily and repeated so much? About 3M per day
  3. Worker.log-2019.mm.dd: Again not certain but has timer activity and another 3M per day.
  4. Name.gmail.com.Blynk.user.2019.mm.dd: appears to have the APPs and their structure - which each user/account has active that day.


  1. Is there any automatic cleanup - or limiting method for the number of days these are retained? They just seem to go forever.
  2. Which file contains SUPERCHART information? Asking because I can setup some Script or such to delete stuff older than say a couple of weeks - but i want to hold SUPERCHART data longer.
  3. Any additional guidance on the various files, usage or the backup/archiving activities?.
  4. I assume dropping my logging to ERROR or INFO will shrink the log per day below the 500M. OR changing update rates - Bbut any other comments?
  5. What is stored at the directory pointed to by "data.folder = " ?

I believe this is stored in your data folder under a subfolder named for your user account email.

I think the first number after history_ is the ID of the project… as listed in the JSON file stored in the file <useremail>.com.blynk.user and visible in the Admin page.


I run periodic SD card backups directly from the Pi desktop… saves on total rebuilding after unscheduled reboot.

I also simply copy my entire Blynk folder across to my PC via VNC every once in awhile… this allows quickly restoring my Local Server on any other device if needed… juts install Java, paste the folder, run the startup script and adjust the IP as needed.

Thanks for the information - great help.

Backup - OH YEA :sunglasses: Definitely needed.

Have already added a “monthly reminder” - don’t want to go through this again. Although all things consider once I understood how things worked - it was fine. Plus I am still a bit linux challenged (ok maybe a lot :crazy_face:)

Thanks again