Thanks Garrett! > 2) it is dependent on an external power source (a little wall wart > provides low voltage power to the card... I don't recall the voltage off > hand)
9V DC. > 3) the contents of the card's DDR ram are never flushed to non-volatile > storage automatically, but require an explicit action from the > administrator to save or restore the contents of the DDR to NAND flash. > (This operation takes 60 seconds, during which the card is not > responsive to other commands.) For the internally developed and RTM OpenSolaris/NexentaStor 3.0 device driver this is not the case, as automatic backup/restore is the default configuration. On host power down/failure the X1 automatically performs a backup, i.e. the DRAM is copied to the on-board NAND (Flash). On the next boot, the NAND is automatically restored to DRAM. This process is seamless and doesn't require any user intervention. *** The hardware support required for automatic backup/restore was not yet available when Garrett wrote the blk2scsa based driver. > 4) the cost of the device is significantly higher (ISTR $1800, but it > may be less than that) than a typical SSD, with much smaller capacity > (4GB) than typical SSD. But it offers much lower latencies and higher > performance than any other SSD I've encountered. The last I checked, the STEC SSD resold by Sun/Oracle, which also correctly implements cache flush, was $6,000. So for SSDs that fully comply with the POSIX requirements for synchronous write transactions and do not lose transactions on a host power failure, we are competitively priced at $1,995 SRP. Christopher George Founder/CTO www.ddrdrive.com -- This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
