On 2 Apr 2015, ste...@agner.ch wrote: > To improve performance we remember the current page in the buffer > and avoid reading it twice. This implicit page cache increases > complexity while does not increase performance in real world cases. > This patch removes that feature. > --- > As discussed in the other patchset... > http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/215802
> ...I did some performance measurements: > Time to "Starting kernel ..." > - without bad block scan & with UBIFS fastmap: 2.02s > - with bad block scan & with UBIFS fastmap: 3.99s > - without bad block scan & without UBIFS fastmap: 4.42s > - with bad block scan & without UBIFS fastmap: 6.38s > Without page cache (with this patch applied): > Time to "Starting kernel ..." > - without bad block scan & with UBIFS fastmap: 2.02s > - with bad block scan & with UBIFS fastmap: 4.01s > - without bad block scan & without UBIFS fastmap: 4.41s > - with bad block scan & without UBIFS fastmap: 6.39s [snip] I also measured 'write performance' with the mtd_speedtest (performing similar patch to the Linux driver) and I see no difference. I think a write benchmark is more appropriate to test this functionality? While at least it seems that neither read nor write is affected by the simplification. Fwiw, Bill Pringlemeir. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
