SD-Driver in mbed OS is having performance issue

[yogpan01]

Description

• Type: Bug
  SD Driver performance is not the same as in freeRTOS. There has been performance improvements done through spi: Add SPI block-write to C++ and HAL for performance #4207 however, accompanied changes that are probably required on the SD-Driver have not implemented/merged/tested yet.
  Based on @sg- 's comments from discussion
  "The last commit was mid-May. It has not yet been updated to use multi-byte write. It’ll be a few more days until someone gets to this. In the meantime, the simplest change to see improvement would be to replace https://github.com/ARMmbed/sd-driver/blob/master/features/filesystem/sd/SDBlockDevice.cpp#L579-L581 with the block write. I’m sure there are other areas that would benefit from this but these are the 2 major areas. And the read section https://github.com/ARMmbed/sd-driver/blob/master/features/filesystem/sd/SDBlockDevice.cpp#L559-L561"

• Related issue: IOTMORF-991

• Priority: Critical

[yogpan01]

@sg- @galc FYI

[sg-]

Fixed by PelionIoT/sd-driver#6, PelionIoT/sd-driver#9, PelionIoT/sd-driver#17, PelionIoT/sd-driver#18, PelionIoT/sd-driver#26, PelionIoT/sd-driver#27

[0xc0170]

Fixed by PelionIoT/sd-driver#6, PelionIoT/sd-driver#9, PelionIoT/sd-driver#17, PelionIoT/sd-driver#18, PelionIoT/sd-driver#26, PelionIoT/sd-driver#27

@yogpan01 Is there any other improvements you are waiting for or anything that we should be aware of?