9 Jul
2005
9 Jul
'05
8:51 p.m.
On Sat, 2005-07-09 at 15:46 -0500, Bryan J. Smith wrote:
Yes, 3Ware cards (prior to the 9000 series) "suck" at RAID-5 writes, because the use a small amount of costly (transistor-wise) SRAM. But using SRAM also means it doesn't need battery backup either.
Let me rephrase that ...
As long as power is delivered to the card, or has been delivered within the last few seconds, the data in the SRAM remains, and can be flushed. This is different than DRAM where you need both A) a logic that refreshes the data B) power to do A
The power usage of SRAM versus DRAM is orders of magnitude.
Now on the Escalade 9000 series, you do need battery backup to guarantee the DRAM is maintained between freezes and lock-ups.
--
Bryan J. Smith b.j.smith@ieee.org
---------------------------------------------------------------------
It is mathematically impossible for someone who makes more than you
to be anything but richer than you. Any tax rate that penalizes them
will also penalize you similarly (to those below you, and then below
them). Linear algebra, let alone differential calculus or even ele-
mentary concepts of limits, is mutually exclusive with US journalism.
So forget even attempting to explain how tax cuts work. ;->