[Drbd-dev] New Features
lars.ellenberg at linbit.com
Sat Sep 20 15:18:21 CEST 2008
On Fri, Sep 19, 2008 at 04:28:19PM -0600, Morey Roof wrote:
> The first item on the list is a write back cache. Now don't run
> screaming to hills yet. In our setup we have the two nodes in two
> different buildings which are feed by different power supplies from the
> city grid. The machines themselves have dual power supplies which each
> power supply going to it's own UPS and circuit. So, we have a good
> redundant power supply setup. So, I was thinking about creating a
> caching system in DRBD to allow for dedicating some of the server's RAM
> to a large read/write-back cache. In the event of communication failure
> between the peers I wanted it to flush the entire cache and then run in
> write-through mode and move back to write-back mode after communication
> is present again and the resync is finished.
> So that is the basic idea. I was thinking about having it use the
> ramdisk system so that you can specify a device that is used as the
> cache. The reason I was thinking about this is that if you happen to
> purchase one of those Gigabyte ram HDD that is just like a large battery
> backed write cache you could set it as the cache device as well.
> What are your thought?
something I though of myself already,
but nothing for the curren drbd architechture.
I sent you my Linux-Kongress 2008 paper off list,
where I scetch what I have in mind for the future.
I'd put in a link here, if I had it online already.
though I did not mention it, a (possibly non-volatile) ram disk
would fit in pretty well as the log device.
let me know what you think.
: Lars Ellenberg
: LINBIT | Your Way to High Availability
: DRBD/HA support and consulting http://www.linbit.com
DRBD® and LINBIT® are registered trademarks of LINBIT, Austria.
please don't Cc me, but send to list -- I'm subscribed
More information about the drbd-dev