yes, a jornaling but using ssd first and sata after it´s not raid feature... it´s per disk filesystem feature... we could implement jornaling in raid too... but´s more inteligent (easy) at application level (filesystem) you could write first at network (if it´s faster than sata) and after at sata (if it´s slower than network) it´s not a raid feature... it´s a per device feature got it? maybe a device (not raid..) for a cache division on devices for example /dev/sda (sata 1terabyte 100mb/s) /dev/sdb (ssd 1gigabyte 1000mb/s) /dev/cache_a (a mix of sata and ssd with sata size 1terabyte, and mixed speed (memory, ssd, sata)) cache_a device should know that early reads/write should be writen to sdb time in time it should sync at sda the same happens with memory (ram memory) but it´s volatille (diferent than ssd that´s not volatille) /dev/sdb should be sync /dev/sda should be async (since /dev/sdb make it safe to use async) that´s you intention? i don´t know if linux have it, anyone know? 2011/1/19 Cory Coager <ccoager@xxxxxxxxx>: > On Wed, Jan 19, 2011 at 02:16:08PM -0200, Roberto Spadim wrote: >> ok, your hardware have: >> cpu, memory, disk controller, disks >> >> and you computer have: >> cpu, memory, disk controler (your hardware) >> >> if your computer cache don?t sync to your disk controller you will >> lose information.... >> >> check that *memory, is the volatille memory and *disk controller is >> the non volatille memory >> if you tell me that you will never have a *memory, and you have always >> a non volatille memory, no problem, you will never need a kernel >> load... just a boot loader that read previous memory information and >> start in that point... why don?t do this? non volatille memory is not >> as fast as volatille memory >> got the problem? > > Sorry, we're still not on the same page. I would use both a ramdisk > and sata disk. The ramdisk would act as a persistent cache > (with the battery) for the sata disks. Enabling write through > would write to the cache first then sync to the sata disks. > > Understand what I'm getting at now? > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Roberto Spadim Spadim Technology / SPAEmpresarial -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
