Re: [Bug-ddrescue] Another bug on -J drives: trim mode is actually scrape mode

[Antonio Diaz Diaz]

address@hidden wrote:
> - The front is read until a bad sector, which locks the drive
> - This first run expands the previous '+' block
> - Next run (after drive restart and ddrescue restart) gets no data
> and the bad sector is marked (Now we have: + - * +)
> - Next run **continues from the front** and either finds new good
> data or adds another
> bad sector to the '-' block - And so forth. *** end of block is never
> trimmed; this is effectively scrape mode ***

True. Maybe ddrescue should trim from the end of the block when it finds 
(- * +), and perhaps mark the block as non-scraped (without trying to 
read it) if it finds (- * -).

I'll do some tests and see what happens.


> If we try using -R reverse, it **still** trims from the front of each
> block. Reverse apparently only affects block sequences, not what
> happens within a block, at least in trim mode.

This is also true for scrape mode because reading forwards is usually 
faster than reading backwards inside a block.


Best regards,
Antonio.