look this:
http://www.ramsan.com/products/4
http://www.ramsan.com/products/2


2011/1/19 Roberto Spadim [off-list ref]:

don´t forget that you can use ramdisks.... just read how to select the
right memory, and the right position before initialize you ramdisk

2011/1/19 Roberto Spadim [off-list ref]:

quoted

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?


2011/1/19 Cory Coager [off-list ref]:

quoted

On Wed, Jan 19, 2011 at 01:19:18PM -0200, Roberto Spadim wrote:

quoted

ok,
but if you don?t sync file system (remove from memory and put in disk
controller)
you will lost information with or without a batery

how to don?t lose information?
don?t power down you memory,cpu, disk controller (sata controler, raid
controller, or anyother) and disks (does it have a batery? a super
capacitor?)
if you power down, be sure that all memory was send to disk controller
and that disk controller have energy (batery or capacitor) to send
information to disks (they need batery or capacitor too)

right?
so, a ups can power cpu, memory, disk controller and disks with only
one batery (not a batery for each device cpu,memory,disk,disk
controller)
the best world could be a non volatile memory (250mb/s flash 4kb
block) with the speed of volatile memory (10000mb/s ddr3 i don?t know
the block size)

It would have to work the same as a hardware RAID controller.
Information is first written to the cache then synced to the
disk.  If the data is in the cache but not on the disk, the
machine loses power, next boot up the software raid would need a
way to flush the data from the ram disk to the disk.  Of course
this would require the battery be in working condition, as with
any hardware.

Hopefully I've explained that well enough.  Perhaps it will be
better to see the hardware I'm talking about:
http://techreport.com/articles.x/16255
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Roberto Spadim
Spadim Technology / SPAEmpresarial

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Roberto Spadim
Spadim Technology / SPAEmpresarial

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Roberto Spadim
Spadim Technology / SPAEmpresarial
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