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- From: richb@jti.com (Richard Braun)
- Newsgroups: comp.os.msdos.misc,comp.os.linux,comp.sys.ibm.pc.hardware
- Subject: SCSI performance / Adaptec vs Seagate
- Message-ID: <C1FwFo.G63@jti.com>
- Date: 26 Jan 93 02:33:21 GMT
- Article-I.D.: jti.C1FwFo.G63
- Sender: news@jti.com (News Admin)
- Organization: Jupiter Technology Inc. / Waltham, MA
- Lines: 18
- Nntp-Posting-Host: bart.jti.com
-
- Using a simplistic disk performance test program provided by a drive
- manufacturer, I came up with the following surprising result:
-
- The 8-bit Seagate ST02 is nearly 3 times faster than the
- 16-bit bus-mastering Adaptec 1542A.
-
- The program measures transfer rate, average seek time, track-to-track
- seek time, and a so-called "performance index". With the drive
- low-level formatted for the Seagate's disk geometry, I get 3.5ms
- track-to-track time and a 30 performance index. Reformatted for the
- Adaptec, the numbers are 4.9ms and 11.6.
-
- Why might this be? Is it the different head/sector mapping (64 vs. 63
- heads, I think), or is the Adaptec just plain slower? Is it possible/helpful
- to optimize the controller/device driver to match the physical disk
- characteristics (15 heads, 1632 cylinders)?
-
- -rich
-