On Monday 09 January 2006 21:53, Trey Boudreau wrote: > On Mon, Jan 09, 2006 at 07:42:28PM -0500, Steve Adeff wrote: > > On Monday 09 January 2006 17:36, Trey Boudreau wrote: > > > On Mon, Jan 09, 2006 at 12:26:18PM -0800, Yeechang Lee wrote: > > > > James C. Dastrup <[EMAIL PROTECTED]> says: > > > > > Is anyone aware of a PCI-X 64bit / 133MHz capable IDE RAID HBA? > > > > > Or, how about a PCI 64bit / 33 Mhz MHz capable IDE RAID HBA? > > > > > > > > People generally consider 3Ware's 7xxx (ATA) and 8xxx/9xxx-series > > > > (SATA) cards, which all support 64-bit/66MHz PCI-X, the standard for > > > > high-quality, reasonably-priced, true hardware RAID cards. (Or just > > > > for JBOD, as I'm doing with two 7506-4 cards and eight 400GB ATA > > > > drives I'm using in part for MythTV.) > > > > > > I *really* like the performance of my Areca ARC-1120 8 port SATA PCI-X > > > card. It beats the pants off of my 3ware 7450 and 8506. I don't know > > > how it compares to the 9xxx-series controllers. Unfortunately, the > > > last time I checked the Areca folks hadn't got their drivers into the > > > kernel tree (2.6.14-mumble). It annoyed me to have to unpack the > > > archive and tweak the Kconfig file, but I eventually got over it > > > (mostly ;-). > > > > > > -- Trey > > > > whoa, $600 for a controller card! I think I can live with software RAID, > > rather spend the money on a faster cpu... > > No amount of CPU cycles will get you the disk bandwidth lost to software > RAID5 back: > > Hardware RAID5 write of one 512-byte disk block: > write 512 bytes over PCI > (controller card updates the parity without causing PCI bus activity) > > Software RAID5 write of one 512-byte disk block: > read 512 bytes of parity over PCI > write 512 bytes of data over PCI > write 512 bytes of modified parity over PCI > > At best you can amortize the parity I/O over "n" blocks, where "n" > equals the number of disks in your RAID5 set minus one. Given MythTV's > propensity for creating large files, you can get this level of > performance much of the time. Even so, you never get those bus cycles > back. > > -- Trey
ahh... true, didn't think of that. I also found a few linux-compatible hardware RAID5 SATA 4+ disc PCI/PCIX/PCIE cards for under $200 on ebay. -- Steve _______________________________________________ mythtv-users mailing list [email protected] http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
