James Richard Tyrer wrote: > I was considering buying a small 1-2 GByte flash disk form my system so > I was looking over what was available and didn't find what I wanted. > > A system based on a CompactFlash memory card is very inexpensive. > However, I find that they are slower than a hard drive :-(. >
The slowness is due to PIO mode, you might want to get a newer revision ide-to-cf convertor, which has DMA support and an appropriate card. > The inexpensive ones are based on the IDE/ATA interface and have a > socket for 1 CF card. It appears that not much is needed for this > interface. Its only wiring :) > I suppose that it might be relevant to know how wide the data bus on the > IDE and CF are. The IDE is 16 bit IIRC and IIUC CF flash is also 16 > bit. So, it appears obvious to me that the speed could be increased by > using the PCI or PCIe interface and using several cards in parallel > (i.e. striping the data). With 32 bit PCI you could use 2 cards striped > in parallel and with 64 bit PCI you could use 4 cards striped in > parallel. It would also be possible to use 2 banks (or 2 disks) the > same as memory so that 32 bit could use 4 cards. Or, 2 disks with 2 > banks each. > > Since this idea is so obvious, I should probably patent it ASAP. :-D > > It probably wouldn't need much besides a PCI controller to implement. > > IIUC, CF cards come in different speeds and (obviously) the speed would > depend on the speed of the cards being used, but it looks like with fast > enough cards (133x?) a 64 bit PCI (or a 32 bit with 2 disks) could beat > SCII 160 or with 2 banks it could beat SCII 320. > > This should considerably speed up a typical desktop Linux system if used > for swap. > Buy a 4 port USB adapter and put there 4 usb sticks and run RAID0 :) or just 4 linux swaps (the kernel swaps to all of them in parallel). I'm currently using this on my diskless desktop (on onboard USB ports), with 1x256MB and its quite slow when it cames to swap. But I have no choice, coz it wont swap to file on NFS mount :/ > Perhaps SD cards are a better idea. > _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
