On Fri, Mar 16, 2018 at 2:59 PM Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > On Fri, 16 Mar 2018 21:51:48 +0000 Wei Wang <wei.vince.wang@xxxxxxxxx> wrote: > > On Fri, Mar 16, 2018, 14:33 Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > > On Fri, 16 Mar 2018 11:25:08 -0700 Wei Wang <wvw@xxxxxxxxxx> wrote: > > > > > > > Change VM_MAX_READAHEAD value from the default 128KB to a configurable > > > > value. This will allow the readahead window to grow to a maximum size > > > > bigger than 128KB during boot, which could benefit to sequential read > > > > throughput and thus boot performance. > > > > > > You can presently run ioctl(BLKRASET) against the block device? > > > > > > > Yeah we are doing tuning in userland after init. But this is something we > > thought could help in very early stage. > > > "thought" and "could" are rather weak! Some impressive performance > numbers for real-world setups would help such a patch along. ~90ms savings from an Android device compared to setting the window later in userland. I was using 'week' words as I agree with Linus's point - it is all about the storage, so the savings are not universal indeed.
