Story: The sorry state of solid state

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Flash Drives, a Bipolar component

I have considerable experience with Flash Drives, especially the Compact Flash, IDE plug-in modules and USB Flash drives.

The biggest problem with Compact Flash Drives and IDE plug-in modules is that the Flash Memory inside is optimized for either READ or WRITE function having the speed advantage over the other. The biggest difference between the two functions is that read operations are highly serial, data is stored one byte after the other. It can be streamed out and output 8 bits in each IDE byte read. 16 bits in an IDE word read. Flash memory setup to allow for fast reads will have a high speed serial to parallel converter function running at a high clock speed and memory block sizes will be large..

To optimize for Write operation, the flash has to be setup for smaller memory blocks so that files can be written as a block. The data being written has to be written as complete blocks even if only one byte needs to be changed in the block. Accessing the block means that all of it must be read into a "mirror" of the block and then the changes are written to the "mirror" and then the modified block is written back to the memory. The write function can take 2 or three reads in addition to the write.

Smaller blocks for write speed will slow down the read function because each block requires a new address to be generated to locate and read the data.

USB drives have the same issue as the Compact Flash form factor but everything stays in serial format in and out of the drive.

My best guess is that the manufacturers went cheap and bought slower parts because Flash memory is still very expensive compared to standard ATA and SATA hardware at the same capacities.

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