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Newsgroups: comp.unix.bsd Path: sserve!manuel.anu.edu.au!munnari.oz.au!spool.mu.edu!umn.edu!The-Star.honeywell.com!sol.ctr.columbia.edu!zaphod.mps.ohio-state.edu!darwin.sura.net!jvnc.net!nuscc!ntuix!eoahmad From: eoahmad@ntuix.ntu.ac.sg (Othman Ahmad) Subject: Re: ISA is faster than EISA ? (Was: Re: DOS and 386BSD (and NT and OS2)) Message-ID: <1992Oct23.010408.29746@ntuix.ntu.ac.sg> Organization: Nanyang Technological University - Singapore X-Newsreader: TIN [version 1.1 PL6] References: <1992Oct22.093459.13824@autelca.ascom.ch> Date: Fri, 23 Oct 1992 01:04:08 GMT Lines: 40 Norbert Bladt (nbladt@autelca.ascom.ch) wrote: : >the SCSI-2. ISA bus is still much faster than any hard-disk controller. : You say, that the EISA bus is too slow for SCSI-2, but the ISA bus is still : faster than any hard-disk controller. It indirectly follows: : : You say that the (16-bit 8Mhz) ISA bus IS FASTER than EISA bus ? NO, I said the "hard-disk controller". I have some figures of a 1Gbyte Hard disk SCSI that has 10MHz sysnchronous and 5 Mhz asynchronous. IDE is only 5Mhz asynchronous. I'm not sure what they actually mean, but I believe very few OS can exploit the synchornous mode, especially for Unix block-oriented fs. : This must be wrong ! : The DMA rate on the ISA bus is about 5 (or 5.7) MB/sec. while on the EISA If you disable this DMA, it can be made faster. The peak for ISA bus is 32 Mhz using the 0WS signal. Similar to the Vesa Local bus architecture, but the Vesa is now 2 times faster by virtue of its 32 bit. Not sure about this though. : bus it is (up to) 33MB/sec. Quite a difference in my opinion. : Did you ever use a system with an EISA bus ? : I have one at home and can tell you it's very fast in accessing the disk ! Can you give some figures. Such as iozone which is more portable. However give details about your Hard-disk controller or SCSI-2 card, the amount of Cache available, etc. : BTW: Thanks for your example of an Xconfig file. I used it to get the : X386mono server running. What card are you using? Many people may be interested. -- Othman bin Ahmad, School of EEE, Nanyang Technological University, Singapore 2263. Internet Email: eoahmad@ntuix.ntu.ac.sg Bitnet Email: eoahmad@ntuvax.bitnet