FatFs performance issue

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by jonas2 on Wed Jul 02 04:13:17 MST 2014

I use FatFs R0.09 on a Cortex M3 microcontroller (LPC1778) in a multitask environment
(Crossworks tasking library).
I've noticed that some FatFs functions take a lot of time executing, e.g.

f_open:     40 ms
f_close      7 ms

Is this what I should expect or can I somehow decrease the processing time these functions "consume". The clock is running @120MHz so there is a lot of instructions needed for these functions.
One solution would be to open all files at startup and never close them so I only need to use f_write and f_read but I'm not sure if that is a correct way to use FatFs. Have anyone used FatFs like that?

Otherwise FatFs works perfectly.