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diff --git a/share/doc/papers/diskperf/equip.ms b/share/doc/papers/diskperf/equip.ms new file mode 100644 index 0000000..264ea04 --- /dev/null +++ b/share/doc/papers/diskperf/equip.ms @@ -0,0 +1,177 @@ +.\" Copyright (c) 1983 The Regents of the University of California. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)equip.ms 6.2 (Berkeley) 4/16/91 +.\" +.ds RH Equipment +.NH +Equipment +.PP +Various combinations of the three manufacturers disk controllers, +and two pairs of Winchester disk drives were tested on both +VAX 11/780 and VAX 11/750 CPUs. The Emulex and Systems Industries +disk controllers were interfaced to Fujitsu 2351A +``Eagle'' +404 Megabyte disk drives. +The DEC UDA50 disk controller was interfaced to two DEC RA81 +456 Megabyte Winchester disk drives. +All three controllers were tested on the VAX 780 although +only the Emulex and DEC controllers were benchmarked on the VAX 11/750. +Systems Industries makes a VAX 11/750 CMI interface for +their controller, but we did not have time to test this device. +In addition, not all the storage systems were tested for +two drive throughput. +Each of the controllers and disk drives used in the benchmarks +is described briefly below. +.NH 2 +DEC UDA50 disk controller +.PP +This is a new controller design which is part of a larger, long range +storage architecture referred to as +``DSA'' +or \fBD\fRigital \fBS\fRtorage \fBA\fRrchetecture. +An important aspect of DSA is migrating a large part +of the storage management previously handled in the operating +system to the storage system. Thus, the UDA50 is a much more +intelligent controller than previous interfaces like the RH750 or +RH780. +The UDA50 handles all error correction. +It also deals with most of the physical storage parameters. +Typically, system software requests a logical block or +sequence of blocks. +The physical locations of these blocks, +their head, track, and cylinder indices, +are determined by the controller. +The UDA50 also orders disk requests to maximize throughput +where possible, minimizing total seek and rotational delays. +Where multiple drives are attached to a single controller, +the UDA50 can interleave +simultaneous +data transfers from multiple drives. +.PP +The UDA50 is a UNIBUS implementation of a DSA controller. +It contains 52 sectors of internal buffering to minimize +the effects of a slow UNIBUS such as the one on the VAX-11/780. +This buffering also minimizes the effects of contention with +other UNIBUS peripherals. +.NH 2 +Emulex SC750/SC780 disk controllers +.PP +These two models of the same controller interface to the CMI bus +of a VAX 11/750 and the SBI bus of a 11/VAX 780, respectively. +To the operating system, they emulate either an RH750 or +and RH780. +The controllers install in the +MASSBUS +locations in the CPU cabinets and operate from the +VAX power suplies. +They provide an +``SMD'' +or \fBS\fRtorage \fBM\fRodule \fBD\fRrive +interface to the disk drives. +Although a large number of disk drives use this interface, we tested +the controller exclusively connected to Fujitsu 2351A disks. +.PP +The controller ws first implemented for the VAX-11/750 as the SC750 +model several years ago. Although the SC780 was introduced more +recently, both are stable products with no bugs known to us. +.NH 2 +System Industries 9900 disk controller +.PP +This controller is an evolution of the S.I. 9400 first introduced +as a UNIBUS SMD interface. +The 9900 has been enhanced to include an interface to the VAX 11/780 native +bus, the SBI. +It has also been upgraded to operate with higher data rate drives such +as the Fujitsu 2351As we used in this test. +The controller is contained in its own rack-mounted drawer with an integral +power supply. +The interface to the SMD is a four module set which mounts in a +CPU cabinet slot normally occupied by an RH780. +The SBI interface derives power from the VAX CPU cabinet power +supplies. +.NH 2 +DEC RA81 disk drives +.PP +The RA81 is a rack-mountable 456 Megabyte (formatted) Winchester +disk drive manufactured by DEC. +It includes a great deal of technology which is an integral part +of the DEC \fBDSA\fR scheme. +The novel technology includes a serial packet based communications +protocol with the controller over a pair of mini-coaxial cables. +The physical characteristics of the RA81 are shown in the +table below: +.DS +.TS +box,center; +c s +l l. +DEC RA81 Disk Drive Characteristics +_ +Peak Transfer Rate 2.2 Mbytes/sec. +Rotational Speed 3,600 RPM +Data Sectors/Track 51 +Logical Cylinders 1,248 +Logical Data Heads 14 +Data Capacity 456 Mbytes +Minimum Seek Time 6 milliseconds +Average Seek Time 28 milliseconds +Maximum Seek Time 52 milliseconds +.TE +.DE +.NH 2 +Fujitsu 2351A disk drives +.PP +The Fujitsu 2351A disk drive is a Winchester disk drive +with an SMD controller interface. +Fujitsu has developed a very good reputation for +reliable storage products over the last several years. +The 2351A has the following physical characteristics: +.DS +.TS +box,center; +c s +l l. +Fujitsu 2351A Disk Drive Characteristics +_ +Peak Transfer Rate 1.859 Mbytes/sec. +Rotational Speed 3,961 RPM +Data Sectors/Track 48 +Cylinders 842 +Data Heads 20 +Data Capacity 404 Mbytes +Minimum Seek Time 5 milliseconds +Average Seek Time 18 milliseconds +Maximum Seek Time 35 milliseconds +.TE +.DE +.ds RH Methodology +.bp |
