On Thu, Jul 3, 2014 at 11:38 AM, Raghavendra K T <raghavendra.kt@xxxxxxxxxxxxxxxxxx> wrote: > > Okay, how about something like 256MB? I would be happy to send a patch > for that change. I'd like to see some performance numbers. I know at least Fedora uses "readahead()" in the startup scripts, do we have any performance numbers for that? Also, I think 256MB is actually excessive. People still do have really slow devices out there. USB-2 is still common, and drives that read at 15MB/s are not unusual. Do we really want to do readahead() that can take tens of seconds (and *will* take tens of seconds sycnhronously, because the IO requests fill up). So I wouldn't go from 2 to 256. That seems like an excessive jump. I was more thinking in the 4-8MB range. But even then, I think we should always have technical reasons (ie preferably numbers) for the change, not just randomly change it. Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>