Re: [PATCH 4.9 069/101] ubi: fastmap: Correctly handle interrupted erasures in EBA

[Lars Persson]

On Mon, Sep 24, 2018 at 8:32 AM Richard Weinberger <richard@xxxxxx> wrote:
>
> Lars,
>
> Am Sonntag, 23. September 2018, 15:49:42 CEST schrieb Lars Persson:
> > Hi Richard
> >
> > Sorry, I assumed this omission from -stable was a mistake.
> >
> > The timing for our boot increased from 45 seconds to 55 seconds on one
> > chip and 42 seconds to 48 seconds on another chip. The regression was
> > completely fixed by applying the extra patches. The way I see it the
> > first patch is a significant slow-down so the second patch is required
> > to restore performance.
>
> okay, this is not good. Let's put the performance patch also into -stable
> to get rid of that regression.
> Usually I'm rather conservative with adding non-trivial material to -stable.
> As history has shown, Fastmap is special. ;-)
>
> Out of interest, what flashes are these? I'm interested in page vs. erase size.
> Did you give UBIFS bulk-read try?
>

Richard, sorry for the late follow-up. Below are the NAND chips that
we use on the affected products.
The products have different NAND timings, some ONFI mode 0 and some
ONFI mode 2, so not lightning fast access to the NAND.

nand: Toshiba NAND 256MiB 3,3V 8-bit
nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 128

nand: Micron MT29F2G08ABAFA 2G 3.3V 8-bit
nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 128

nand: AMD/Spansion S34ML04G2
nand: 512 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size: 128

- Lars