+Arindam (This is the patch set I mentioned) On Fri, Apr 15, 2011 at 2:10 AM, Andrei Warkentin <andreiw@xxxxxxxxxxxx> wrote: > On Thu, Apr 14, 2011 at 6:18 PM, Chris Ball <cjb@xxxxxxxxxx> wrote: >> >> If we've seen a card that freaks out and loses significant bandwidth, that >> would be a good reason to start with a whitelist. If all the data we have >> suggests that it's performance-wise either a win or a no-op, that's a fine >> reason to push it to mmc-next with a blacklist approach and change our >> minds later if our knowledge gets updated. Does that help? >> > > Yes, it does, thanks! Basically so far - > > (a) amazing boost for Sandisk eMMCs > (b) synthetic tests showed no-op for Toshiba (a derivative of Arnd's > flashbench, I'll put it up on GitHub as soon as my hands get to it), > but more realistic test (via SQLite transactions on top of fs) showed > slight deterioration. I'm bringing it up with the vendor to get a > clear picture why and if they are doing anything to address it. > (c) I am going to try to dig up some discrete MMCs (hard beasts to > come by these days) and try with that. > (d) I am going to dig up a few SDXCs and try them out. > > My current theory is that the CMD23 for multiblock should have no > effect on the really braindead cards, and could have deterioration on > cards that somehow optimize the CMD12 path (for example, the T eMMC > optimize consecutive multiblock writes). > > At any rate, I'll decouple CMD23 support from multiblock CMD23 use... > > Yunpeng, I'm curious, what vendors did you have in mind when you > suggested in your original email to use the CMD23 multiblock stuff? > > Thanks again, > A > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
