On Friday 13 August 2010 16:10:24 Ben Chociej wrote: > It's a good point, of course. Ideally we would be able to prioritize > data and place them on 15k versus 7.2krpm disks, etc. However you get > to a point where's there's only incremental benefit. For that reason, > the scope of this project was simply to take advantage of SSD and HDD > in hybrid. Of course, you could register the same complaint about the > ZFS SSD caching: why not take advantage of faster vs. slower spinning > disks? Unfortunately it just wasn't in the scope of our 12-week > project here. > > That's not to say it *shouldn't* be done in the future, of course! > And, incidentally, you could hack it together at this point by setting > the /sys/block/<blockdev>/queue/rotational flag to 0 and using it like > an SSD. :) Then why not make the devices with rotational at 0 be the default "SSDs" but allow the admin to set manually others, without hacking? You can have SSDs in a hardware RAID array, this way the kernel may not know if the block device is on flash media or on rotational media... -- Hubert Kario QBS - Quality Business Software ul. Ksawerów 30/85 02-656 Warszawa POLAND tel. +48 (22) 646-61-51, 646-74-24 fax +48 (22) 646-61-50 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
