Mark Lord wrote: > Gentoopower wrote: >> Raz Ben-Jehuda(caro) wrote: >>> i am thinking of buying a promise card sataII pcix. >>> they have two types, a card which support NCQ >>> and another that does not. >>> What is the bennifit of buying a card with NCQ tagging ? >>> >> How about: http://en.wikipedia.org/wiki/Native_command_queueing > > Yuck.. what a lousy wiki entry. > > NCQ vs. TCQ: NCQ has a much more efficient low-level protocol, > making the host-side (controller, operating-system) quite a bit > simpler than with NCQ. > > Both use 32-deep queue depths, and neither of them are worth a > damn on Linux yet. Except possibly in the libata ahci driver, > or vendor-provided drivers (open source, even) for some chipsets. > > In theory, NCQ/TCQ can speed up a very busy fileserver that is > handling mostly tiny I/O requests. Practically no measurable > benefit for single-user systems. That's a lousy comment:-) Single-User systems can have lots of I/O requests too. If I compile something in the backround, listen to music, while copying files from one drive to the other. I also have lots of I/O while booting. I have two seagates in my box a 160GB 7200.7 and 160GB 7200.9(SATAII NCQ), using NFORCE4. I can defintely feel the speed difference between the two drives. P.S. Just waiting to see NCQ support for my nforce system in libata:-) > > Cheers > - > : send the line "unsubscribe linux-ide" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > > ___________________________________________________________ Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de - : send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
