os/doc
3
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Replace all contractions with their normal form.

Browse source 
Approved by:	nik
This commit is contained in:
Giorgos Keramidas 2001-10-16 12:14:00 +00:00
parent cd9bff24c3
commit 6c15b3e8c9
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=10952
1 changed files with 11 additions and 11 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
en_US.ISO8859-1/articles/storage-devices/article.sgml
View file

@ -20,7 +20,7 @@
</author> </author>
</authorgroup> </authorgroup>
<pubdate>$FreeBSD: doc/en_US.ISO8859-1/articles/storage-devices/article.sgml,v 1.1 2001/07/13 22:30:40 murray Exp $</pubdate> <pubdate>$FreeBSD$</pubdate>
<abstract> <abstract>
<para>This article talks about storage devices with FreeBSD.</para> <para>This article talks about storage devices with FreeBSD.</para>
@ -282,7 +282,7 @@
Instead, it has device drivers that talk directly to the Instead, it has device drivers that talk directly to the
hardware.</para> hardware.</para>
<para><emphasis>So: don't use spare sectoring, bad block remapping <para><emphasis>So: do not use spare sectoring, bad block remapping
or whatever it may be called by the controller manufacturer when or whatever it may be called by the controller manufacturer when
you want to use the disk for FreeBSD.</emphasis></para> you want to use the disk for FreeBSD.</emphasis></para>
</sect3> </sect3>
@ -876,7 +876,7 @@ disk wd3 at wdc1 drive 1</programlisting>
invent. One of the most common mistakes is for people with invent. One of the most common mistakes is for people with
wide-SCSI host adapters to connect devices on all three connecters wide-SCSI host adapters to connect devices on all three connecters
(external connector, internal wide connector, internal narrow (external connector, internal wide connector, internal narrow
connector). Don't do that. It may appear to work if you are connector). Do not do that. It may appear to work if you are
really lucky, but I can almost guarantee that your system will really lucky, but I can almost guarantee that your system will
stop functioning at the most unfortunate moment (this is also stop functioning at the most unfortunate moment (this is also
known as <quote>Murphy's law</quote>).</para> known as <quote>Murphy's law</quote>).</para>
@ -925,7 +925,7 @@ disk wd3 at wdc1 drive 1</programlisting>
own on-board BIOS. During system startup, the SCSI BIOS takes own on-board BIOS. During system startup, the SCSI BIOS takes
over the hard disk interface routines from the system BIOS. To over the hard disk interface routines from the system BIOS. To
fool the system BIOS, the system setup is normally set to No hard fool the system BIOS, the system setup is normally set to No hard
disk present. Obvious, isn't it?</para> disk present. Obvious, is it not?</para>
<para>The SCSI BIOS itself presents to the system a so called <para>The SCSI BIOS itself presents to the system a so called
<emphasis>translated</emphasis> drive. This means that a fake <emphasis>translated</emphasis> drive. This means that a fake
@ -1565,12 +1565,12 @@ Mar 29 21:16:37 yedi /kernel: st1: Archive Viper 150 is a known rogue </screen>
7,200RPM drives of one or two model generations ago. The number 7,200RPM drives of one or two model generations ago. The number
to find on the spec sheet for bandwidth is <quote>internal data to find on the spec sheet for bandwidth is <quote>internal data
(or transfer) rate</quote>. It is usually in megabits/sec so (or transfer) rate</quote>. It is usually in megabits/sec so
divide it by 8 and you'll get the rough approximation of how much divide it by 8 and you will get the rough approximation of how much
megabytes/sec you can get out of the drive.</para> megabytes/sec you can get out of the drive.</para>
<para>(If you are a speed maniac and want a 10,000RPM drive for your <para>(If you are a speed maniac and want a 10,000RPM drive for your
cute little PC, be my guest; however, those drives become cute little PC, be my guest; however, those drives become
extremely hot. Don't even think about it if you don't have a fan extremely hot. Do not even think about it if you do not have a fan
blowing air <emphasis>directly at</emphasis> the drive or a blowing air <emphasis>directly at</emphasis> the drive or a
properly ventilated disk enclosure.)</para> properly ventilated disk enclosure.)</para>
@ -1582,7 +1582,7 @@ Mar 29 21:16:37 yedi /kernel: st1: Archive Viper 150 is a known rogue </screen>
lower average seek times, but also the rotational delay is one lower average seek times, but also the rotational delay is one
place where slow-spinning drives can never beat a faster one. place where slow-spinning drives can never beat a faster one.
(The average rotational latency is half the time it takes to (The average rotational latency is half the time it takes to
rotate the drive once; thus, it's 3 milliseconds for 10,000RPM rotate the drive once; thus, it is 3 milliseconds for 10,000RPM
drives, 4.2ms for 7,200RPM drives and 5.6ms for 5,400RPM drives.) drives, 4.2ms for 7,200RPM drives and 5.6ms for 5,400RPM drives.)
Latency is seek time plus rotational delay. Make sure you Latency is seek time plus rotational delay. Make sure you
understand whether you need low latency or more accesses per understand whether you need low latency or more accesses per
@ -1614,7 +1614,7 @@ Mar 29 21:16:37 yedi /kernel: st1: Archive Viper 150 is a known rogue </screen>
<para>Most SCSI drives sold today are of 3.5" form factor. They <para>Most SCSI drives sold today are of 3.5" form factor. They
come in two different heights; 1.6" (<quote>half-height</quote>) or come in two different heights; 1.6" (<quote>half-height</quote>) or
1" (<quote>low-profile</quote>). The half-height drive is the same 1" (<quote>low-profile</quote>). The half-height drive is the same
height as a CDROM drive. However, don't forget the spacing rule height as a CDROM drive. However, do not forget the spacing rule
mentioned in the previous section. If you have three standard mentioned in the previous section. If you have three standard
3.5" drive bays, you will not be able to put three half-height 3.5" drive bays, you will not be able to put three half-height
drives in there (without frying them, that is).</para> drives in there (without frying them, that is).</para>
@ -1634,15 +1634,15 @@ Mar 29 21:16:37 yedi /kernel: st1: Archive Viper 150 is a known rogue </screen>
<para>On the other hand, if you need to connect many drives, going <para>On the other hand, if you need to connect many drives, going
for Fast-wide SCSI may not be a bad idea. That will have the same for Fast-wide SCSI may not be a bad idea. That will have the same
max bandwidth as Ultra (narrow) SCSI, while electronically it's max bandwidth as Ultra (narrow) SCSI, while electronically it is
much easier to get it <quote>right</quote>. My advice would be: if much easier to get it <quote>right</quote>. My advice would be: if
you want to connect many disks, get wide SCSI drives; they usually you want to connect many disks, get wide SCSI drives; they usually
cost a little more but it may save you down the road. (Besides, cost a little more but it may save you down the road. (Besides,
if you can't afford the cost difference, you shouldn't be building if you can not afford the cost difference, you should not be building
a disk array.)</para> a disk array.)</para>
<para>There are two variant of wide SCSI drives; 68-pin and 80-pin <para>There are two variant of wide SCSI drives; 68-pin and 80-pin
SCA (Single Connector Attach). The SCA drives don't have a SCA (Single Connector Attach). The SCA drives do not have a
separate 4-pin power connector, and also read the SCSI ID settings separate 4-pin power connector, and also read the SCSI ID settings
through the 80-pin connector. If you are really serious about through the 80-pin connector. If you are really serious about
building a large storage system, get SCA drives and a good SCA building a large storage system, get SCA drives and a good SCA