[rrd-users] Confusion about VDEF total and graph values

Pavel Ruzicka pavouk at pavouk.org
Fri Oct 14 14:56:12 CEST 2016

Hi Arjan,

> but from a functional point of view I don't think it
> matters. It would help on some I/O, CPU and in the end probably will make
> my SD Card in the raspberry PI live longer (the rrd file is being allocated
> in advance  so the gas value will be written at the same location on the SD
> Card many times per hour in my case, right?).

Most of new SD cards use "wear leveling" that if your system will write to 
same place on the filesystem that controller in the card wrote data everytime 
to another place.
For bigger lifetime it is a good idea to have Flash not full.

Also it is a good idea to use "Industrial grade" SD card which use SLC chips 
instead MLC or TLC chips at normal flash cards and have much bigger number of 
writes to cells.

Best regards,


More information about the rrd-users mailing list