Re: ZFS melting under postgres...

Ivan Voras wrote:
David Duchscher wrote:
On Dec 14, 2007, at 6:57 AM, Dag-Erling Smørgrav wrote:

David Duchscher <daved@xxxxxxxx> writes:
So does anybody know of a battery backed NVRAM card that can be used
with FreeBSD that the ZIL could be offloaded to?
Any CF card or similar will do. You don't need battery backup for
flash memory.
I did think of that but is a CF card faster than a good SAS or SATA
drive?

Not in transfer rate, but it could help hugely with seek-intensive IO
loads (since seeks are instantaneous on flash or other solid-state
drives). In theory, they could be of immense benefit for databases and
seek-intensive operations on file systems, but the limited bulk transfer
rates and relatively small sizes (for decent money) currently prevent
their wide-spread use.

That's no longer true. You can't get more than 5-10MB/s from seek-intensive RAID0 with two 15K drives, while 20-30MB/s is not a problem for the comparable priced/sized SSD drive.

-Maxim
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