kdq@demott.COM (Kevin D. Quitt) (07/20/90)
Be careful about the "doubled" tape capacity. One Exabyte OEM
mentioned this to me and explained that it was achieved by compressing
the data before it was being stored. Since what we put on tape is
already compressed, we won't see any such gain.
--
_
Kevin D. Quitt demott!kdq kdq@demott.com
DeMott Electronics Co. 14707 Keswick St. Van Nuys, CA 91405-1266
VOICE (818) 988-4975 FAX (818) 997-1190 MODEM (818) 997-4496 PEP last
96.37% of all statistics are made up.dwells@fits.acc.Virginia.EDU (Don Wells) (07/21/90)
In article <413@demott.COM> kdq@demott.COM (Kevin D. Quitt) writes: > > Be careful about the "doubled" tape capacity. One Exabyte OEM >mentioned this to me and explained that it was achieved by compressing >the data before it was being stored. I suspect that there is some confusion going on here. True, compression options are going to appear for essentially *all* of the cartridge devices. BUT! Several of the media are not operating at their theoretical limits in packing density. The Digidata 12.5mm cartridges and the Exabyte 8mm cartridges are in this category, and both are capable of density doubling. My understanding was that the Exabyte 5_GB option is a real doubling. >Since what we put on tape is >already compressed, we won't see any such gain. If you are right that the Exabyte 5_GB option is simply compression, then there will be no gain on data that is already compressed. >Kevin D. Quitt demott!kdq kdq@demott.com >DeMott Electronics Co. 14707 Keswick St. Van Nuys, CA 91405-1266 >VOICE (818) 988-4975 FAX (818) 997-1190 MODEM (818) 997-4496 PEP last There is another rumor about the Exabyte 5 GB option that I have heard: 5_GB drives cannot read/write 2.3_GB tapes! Donald C. Wells, Associate Scientist | NSFnet: dwells@nrao.edu [192.33.115.2] National Radio Astronomy Observatory | SPAN: NRAO::DWELLS [6654::] Edgemont Road | BITnet: DWELLS@NRAO Charlottesville, VA 22903-2475 USA | UUCP: ...!uunet!nrao.edu!dwells Lat: 38:02.2N Long: 78:31.1W | Tel:+1-804-296-0277 Fax:+1-804-296-0278
kdq@demott.COM (Kevin D. Quitt) (07/21/90)
In article <1990Jul20.193412.18146@murdoch.acc.Virginia.EDU> dwells@fits.acc.Virginia.EDU (Don Wells) writes: >In article <413@demott.COM> kdq@demott.COM (Kevin D. Quitt) writes: >> >> Be careful about the "doubled" tape capacity. One Exabyte OEM >>mentioned this to me and explained that it was achieved by compressing >>the data before it was being stored. > >I suspect that there is some confusion going on here. >Exabyte 5_GB option is a real doubling. > >>Since what we put on tape is >>already compressed, we won't see any such gain. > >If you are right that the Exabyte 5_GB option is simply compression, >then there will be no gain on data that is already compressed. > Let me be quick to point out that this is what I was told by a marketing/ sales person from the OEM, and not to be considered authoratative. I only meant that people should be aware of what was going on, not to just assume that they're getting what they think they're getting. -- _ Kevin D. Quitt demott!kdq kdq@demott.com DeMott Electronics Co. 14707 Keswick St. Van Nuys, CA 91405-1266 VOICE (818) 988-4975 FAX (818) 997-1190 MODEM (818) 997-4496 PEP last 96.37% of all statistics are made up.