SD info and benchmarks (was Re: EOS M3 porting)

Got it working!  My romcode.dis ramcode.dis was generated with incorrect address parameters.
My cheap kingston SD card maxes out at 10MB/s without CHDK and 9MB/s with CHDK.

The fact it shows "MEDIA_TYPE_SD:1.8V Support" without CHDK but not with confirms that the workaround is needed for proper UHS initialization, regardless of whether this particular card shows a speed benefit.

A new Card (SanDisk Extreme SDHC 32GB UHS-I) gives me more than 52Mbyte writing with RAW Data. 

Measured without CHDK gives nearly same results.
Plotted is the difference of the timestamps in the RAW data (which is more accurate than 1s). Once with 64GB Samsung EVO Plus and with SanDisk Extreme SDHC 32GB UHS-I. RAW File size around 24MByte

My last idea this year: 
Maybe a benchmark could perform a sd_performance_value for dynamic sleep() calculation
or a warning like "some Features are limited / dangerous / not available due to slow card" ?