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- Path: sparky!uunet!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!rutgers!att-out!cbnewsl!rl
- From: rl@cbnewsl.cb.att.com (roger.h.levy)
- Newsgroups: comp.sys.ibm.pc.hardware
- Subject: Re: Fast hard drives - seek isn't everything.
- Message-ID: <1992Dec25.171206.28245@cbnewsl.cb.att.com>
- Date: 25 Dec 92 17:12:06 GMT
- References: <BzGu6r.811@sunnup.MAGDATA.COM>
- Distribution: na
- Organization: AT&T Bell Laboratories
- Lines: 59
-
- In article <BzGu6r.811@sunnup.MAGDATA.COM>, beemer@sunnup.MAGDATA.COM (Oscar the Grouch) writes:
- > In article <1992Dec17.092641.24824@doug.cae.wisc.edu> keiths@cae.wisc.edu (Keith Scidmore) writes:
- > >
- > >I asked Hard Drives Intl for their fastest IDE drive (thinking I would
- > >let Zeos keep the Seagate 3283A 245MB drive that came with my system
- > >and upgrade immediately).
- > >HDI sent me a $1000 FJ2624A 510MB Fujitsu IDE drive.x
- >
- > So they sent you what you asked for the disk with the fastest published specs.
- >
- > >It turned out to be slower than the Seagate on
- > >all the benchmarks and programs I tested even though it had about
- > >an 8 ms seek time to the Seagate's 11 ms. The following explains
- > >how this was determined and why the Seagate was faster on both
- > >the benchmarks and on real programs.
- > >
- > >The Seagate was 10-20% faster than the Fujitsu on all my program test. The
- > >reason is that the Fujitsu drive was about 18% faster on seek times but the
- > >Seagate was about 50% faster in transferring the data. I returned the
- > >Fujitsu to HDI.
- > >
- >
- > So who paid for your learning experience. Sounds like HDI did.
- >
- > >First, transfer speed is significant in
- > >choosing a drive. The Fujitsu's 8 ms average seek time (measured) didn't
- > >make it faster. The Fujitsu should have had the additional advantage in that
- > >the software on the larger disk takes less of a percentage of the platters
- > >and the seeks should have been a smaller percentage of the total stroke.
- > >
- > >Second, HDI doesn't always know what they are talking about.
- >
- > What they told you was what you asked for the published stats.
- >
- > >They were inaccurate in telling me the stats of both drives. My tests
- > >showed that the Seagate Drive on my Zeos 486-66 VLB machine ran faster
-
- > So let me guess, after installing the disk, beating hell out of it with
- > your testing program, and using it for some unmentioned period of time
- > you returned it for a full refund. Not; because the drive was defective.
- > Not because it did not meet the published specs. but because it did not
- > live up to your expectations.
-
- I agree that Keith has abused HDI's highly customer oriented policies.
- Also, Keith hasn't said enough to convince me that his testing was
- well controlled. The fact that he didn't previously even understand
- the signficance of rotational latency casts a lot of doubt on his ability
- to insure that all other factors were equal. For example, the specs I
- have say the Fujitsu has a segmented 240KB read-ahead cache that "can
- be configured to further optimize drive performance and [provide] even
- faster data throughput." Did you take a look at configuring the cache,
- Keith? At 4400 RPM and a rotational latency of 6.8 msec, the Fujitsu
- drive SEEMS to have been engineered with transfer rate in mind. I am
- more impressed by HDI's recommendation and the fact that Box Hill selected
- the SCSI version of this drive for their RAID systems than I am with
- Keith's apparently uninformed poking around.
-
- Roger Levy
- Murray Hill, NJ
-