On 31 March 2012 04:24, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Friday 30 March 2012, Zach Pfeffer wrote: >> Last I read Transparent Huge Pages are still paged in and out a page >> at a time, is this or was this ever the case? If it is the case should >> the paging system be extended to support THP which would take care of >> the big block issues with flash media? >> > > I don't think we ever want to get /that/ big. As I mentioned, going > beyond 64kb does not improve throughput on most flash media. However, > paging out 16MB causes a very noticeable delay of up to a few seconds > on slow drives, which would be inacceptable to users. > > Also, that would only deal with the rare case where the data you > want to page out is actually in huge pages, not the common case. What I had in mind was being able to swap out big contiguous buffers used by media and graphics engines in one go. This would allow devices to support multiple engines without needing to reserve contiguous memory for each device. They would instead share the contiguous memory. Only one multimedia engine could run at a time, but that would be an okay limitation given certain application domains (low end smart phones). > > Arnd -- Zach Pfeffer Android Platform Team Lead, Linaro Platform Teams Linaro.org | Open source software for ARM SoCs Follow Linaro: http://www.facebook.com/pages/Linaro http://twitter.com/#!/linaroorg - http://www.linaro.org/linaro-blog -- 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
