阵列卡scsi阵列卡使用（SCSI array card usage）

scsi阵列卡使用SCSI array card usage

Data: SCSI array card usage

SCSI I think the macro advantage is mainly reflected in thespeed, the speed is not a lot of friends directly take SISOFTor other software to test out the results. This is not a simplesense, refers to the load capacity in multi program and tasksituations quickly! Now people are using computer 6,7 thingsat the same time. Especially now BT download more prevalenttoday to SCSI provides a.Bt space to show its mettle can alsodownload upload download, we all love at the same time to openn BT thread, so the loss of the hard disk is quite powerful,and the response time of the system will be more and more slowly.SCSI system and SCSI disk is IDE. The most abnormal leisurelesswhen I opened more than 20 BT at the same time to download andupload, the system response is still smooth, of course is theuse of 160 array RAID0.

Here we come to understand the basic knowledge of SCSI and gradediscrimination

SCSI means small computer interface, as long as the ordinarycomputer to add a PCI SCSI card can be connected to the SCSIdisk, if C is to start with the SCSI disk, as long as the hostof the CMOS set the first boot can be set to scsi. No specialrequirements for hosting or other surrounding areas. Nor doesit affect the simultaneous use of other ide devices. A doublepass SCSI can connect up to 30 disks at the same speed. A singlepass 160 SCSI card can connect 15 simultaneous disks. The speeddoes not affect each other, and only takes one irq. Compare withcommon IDE hard disk, sum up several advantages:

1. scsi can support multiple devices, SCSI-2 (fast SCSI) canreceive up to 7 SCSI devices, ultra2 and ultra3 double pass canconnect 30 SCSI devices. Single pass to 15 disk. That is to say,all devices need to occupy only one IRQ, and SCSI supports awide range of devices such as CD-ROM, DVD, CDR, hard disk drives,tape drives, scanners, and so on.

2. scsi also allows data to be searched by another device whiledata is being transmitted to a device. This allows for higherperformance in multitasking operating systems such as Linux andwindows nt.

3. scsi occupies a very low CPU, and it does have a distinctadvantage in multitasking systems. Because the SCSI card withCPU, can handle all SCSI equipment affairs at work as long asthe host CPU to the SCSI card issuingwork orders, the operationof the SCSI card will have their own work, after the end of thereturnresults to the CPU, in thewhole process, CPU canbe theirown work.

The 4. scsi device is also intelligent, and the SCSI card itselfcan queue up the CPU instructions, thus increasing workefficiency. In multi tasking, the hard disk will be in thecurrent head position, and the adjacent tasks will be completedfirst and then processed one by one.

5. now the fastest SCSI bus has the bandwidth of 320mb/s, whichrequires the use of a 64 bit 66MHz (166MHz) PCI slot, but themaximum speed on ordinary PCs can also reach 133mb/s (more than1-5 points are posted, the other mistakes I made some changes)

6. Now the high-end SCSI disk, 10k/15k single disk speed testhas been close to or more than 2 7200 RPM mainstream IDE harddisk raido way. But the SCSI disk is also sub grade, the generalmodel is faster and faster, noise and temperature control isbetter. For example, Seagate to do a series of leopard toalgebraic points, leopard 1-7 generations, type mantissarepresents algebra, such as st318705lc behalf of the leopard,the 5 generation 18G, C behalf of the 80 pin server hot pullcheck, if it is w, the end of the 68 represents the needle. Thelatest fifteen thousand turn stx15 model is the same, such asst336752lw onbehalf of 36gx152 generation. The leopardbeforethe disk is SCSI 7200 RPM disc Barracuda series. Fujitsu' s SCSIdrive is known for its speed, quiet and low temperatures. Theappearance is more gentle and affinity than Seagate, andconforms to her characteristics. The mainstream model is sortedby the last letter of the alphabet, slightly different from theseagate. Man318mc stands for man18g 80 needles,

If yes, the man318mp stands for 18G 68 pins. First, MAH, andthen maj, after the man, and f inally mam. Man and mam are thelatest high-end disk, equipped with 8MB buffer, in which mamis 15K, and x15ii quite.

7. The newer SCSI hard disk has only------68 pins and 80 pinsin its interface mode (the old disk has 50 pins, which is themost obvious one in the early days of SCSI, and some friendsstill use it) . The design principle of 80 pin is provideddirectly to the hot swappable module server, support hot plug.The 68 pin is for ordinary PC users, do not support direct hotswap. 80 pin disk can also be used in the ordinary desktop (which

I use and promotion) , only need to add a LVD adapter 80 to 68can, occasional blackouts or careless hot plug do not worry.Adapter must be of good quality, otherwise, even if the U160disk has become 40MB, of course, the quality and price isproportional to. Ordinary boss there, is the way se 40MB adapteradapter and LVD from the appearance of the ordinary se oftennot much difference, the only way is connected with the hangingwall * after use, 2 indicators, one is to look at the displayspeed, the two is to look at the test data. Some people worrythat switching will affect speed, but the actual test resultsare the same.

8. SCSI and IDE are slightly more complex than settings, andif you have more than 2 disks on one channel, you need to assignID, just as a few brothers are queuing up. Otherwise, a dishcannot be identified. The jumpermethodof the 80pin is carriedon the adapter head. The 68 pin disk is made on the jumper ofthe hard disk body. If only one hard disk is attached. Jumpersare not necessary. Ido is the default startup disk, and theother ID is a non startup disk. The SCSI channel takes a id7by default. SCSI channels are automatically terminated withoutadditional termination and can also be taught to be usedsteadily. In the SCSI disk, however, the end signal is safe andreliable, so the top LVD line has many bulls, with terminatorsat the end, fixed terminators and active terminators.

9. The so-called LVD means low voltage transmission, becauseto achieve the theoretical speed of 80/160, it must be LVD,written in English: low, voltage, differential, LVD, 80mb and160MB, as well as the latest 320mb. LVD uses 2 signal lines asone group for signal transmission, one of which is at high

potential and the other is at low potential. If one of thereceiving signals is to recognize the change of the potential,a high and low voltage must be applied to the two linesrespectively. This way, when both sides are disturbed, they cancancel the interference parts and maintain normal datatransmission, while also expanding the identifiable criticalrange of the signal. But the premise of LVD' s approach is toensure that the two lines are equal to the source ofinterference, so the two signal lines must be bundled together(just like a twisted pair used in LANs) . It should be twistedflat linewithreal LVD, someU160wire is purely for the purposeof saving cost. Afterusing it, although it is possible to workproperly, the wiring length of 25m can not be guaranteed.

10. Double u160lvd channel SCSI and single u160lvd channel SCSIdifference: Double 160 is 2 160 parallel channels, each channelcan dial 1-15 U160 disk, and single U160 card is aU160 channel,and the other is 40MB channel. The 2 is not a grade, double passsingle card a lot more expensive than.

11. Said so much, if more complex, simply said SCSI +LVD+LVDis to use LVD SCSI card line can be composed of fast, stablein your ideal SCSI system, durable, especially audio, video andnon people have to use SCSI disk to ensure not to drop frame.The use of IDE to NLE is a very painful and even cannot do.

12. So what are the salient benefits of using SCSI for regulargamers? A. When moving copied data, you can obviously feelfaster than ide.

For example, copying a460mb file to a SCSI disk takes only about

more than 20 seconds (of course, this is the best disk speedat a single file) . B. We all know that the C system has frequentdata search and read and write fragments and discontinuousspace, the practice shows that the IDE disc in the system isused for a long time (such as one month defragmentation andspace)will obviously feel the slowresponse timeof the system,and SCSI system connection this feeling almost no longer! C.Can do a lot of things at the same time, have tried to listento MP3, play q3/cs, the background is still open 2, 3 copiesof the window and a number of IE window? The obvious feelingis copying large files among partitions, the advantages of SCSIand speed on the performance thoroughly the nephew. D. But thatis, if the system is purely from the time or time to start thesystem SCSI and the merits of IDE, then you get the results youwill be disappointed, because the IDE disk is often SCSI thanthe 7200 turn at this point a little slower, unless the 15K diskis the latest. Those who only pay attention to these 2 pointssuggest not buying scsi. Our approach is generally to take SCSIdisk as a system, while using ide as backup disk. Of course,if you spend more money, abandon IDE disk, no one accused you,SCSI although more expensive than IDE, but value for money,especially suitable for heavy workload occasions, such asInternet cafes. Moreover, now the new second-hand SCSIequipment is only about half of licensed goods. Ha-ha。

13. Buy SCSI disk, pay attention to distinguish between the oldmodel of thick plate or the old type of thin plate, this kindof disk cheap, often let you echocardiography. Evena thin platecan disappoint you. Some of the elimination disk is thick disk,equivalent to 2 ide piledup, but also high point, although someare U160 interface, 4MB cache, but the speed can not be expected

soon. Especially the noise, I have seen that IBMU160has a thickdisk, in the case or to prepare a scare, the noise estimationthan the U.S. combat helicopter sounds odd Longbow arbor is nosmall, the entire desktop in shock, but the price is cheap, 36ghe sold only 360 yuan. Speaking of noise, Fujitsu is the bossin this respect! His maj/man/mam series works like a quiet IDEhard drive, and many times I can't tell whether it' s the IDEor the SCSI disk. The new SCSI are as thick and thin as the IDEhard disk, and the difference is that the appearance of SCSIis more dazzling! Circuit board is IDE, no more than, more cachechip, CPU, a large number of high-grade electricity and so on.Followed by brand considerations, SCSI manufacturers do nothave much, and for a long time, and formed a heart of SCSI prosand cons. Seagate, Fujitsu, Hitachi is a big manufacturer ofquantum, mainly HP, Compaq, DELL and other brands of SCSI serverdisk more for their OEM disk. Among them, Seagate and Fujitsu,themost, theyare theboss. IBM has its ownSCSI disk, typicallyultra, star, ddys, and IC35, which is not as good as SCSI' s inperformance and temperature, noise control, and bad disk rates.The above summary is purely personal experience and experience.There is something wrong, please advise, discuss each other,my purpose is to "SCSI" to the popularity of the people' s homes~! Everyone to feel the charm of SCSI "^ ^ a double pass 160card + 4 eServer leopard 18G working state, which while thereare other devices including the PCI sound card, there is a 30gIDE hard disk, the host is via kt133a but with SD memory chipof the host. But such a SCSI system is better than using P4 2.4GA + two 7200 turn ide raido mode is also strong!

Installation of SCSI necessary knowledge and driver download:

[recommended] opening special tips:

Ordinary users strictly prohibit the use of SCSI card, its ownBIOS in the format function, it belongs to low-level format,the use of more than 99%of the SCSI disk can not be restored!Avoid! Remember! Especially not a sudden interruption or heavyprice in the process, the disc slows down the abnormalconditions in the speed before considering the price.

A.

First insert the card connected after the boot should have SCSIcard information and BIOS detection indicated that BIOS setshortcut keys, generally donot need to enter theBIOS settings,the default is the best time. Unless youwant to have hard diskphysical bad sectors detected by SCSI verify.

Detection of B. search after 15 ID (if it is a double channelcard will search has 15 ID 2 channels) , can correctly identifythe disk type, capacity, synchronization rate, bandwidth mode.The first time C. SCSI system, our approach is generally thefirst to connect the card, disk, enter the old system beforethe recommendation system is windows 2000/xp, find the carddriver in 2k/xp, partition and quick format use Disk Manager.(Win2K has a powerful disk manager position in "my computer"right click on the -----> management -----> disk management.Note: there are many of my friends say can not find SCSI disk,installed in the system is in fact the reason is very simple,not the disk is broken, nor the system does not recognize thedisk, because the system is to go through the disk signature

and marking it can be displayed in the explorer. These are tobe carried out in the disk management.

D. if you want to use SCSI to do system startup, mainly in the2k/xp Disk Manager quick partition and format, remember toactivate the boot to do the diskC zone, this principle andDOSunder the same fdisk, set active.

E. in addition to adaptec products, such as lsi53c1010 initioor other qlogic SCSI card in 2K or XP, the first time after thereset, need to press the F6 button, follow the prompts inadvance for the floppy disk drive SCSI. Otherwise there willbe a full screen blue screen tips: inaccessible unknowharddrive. . . . . .

F: if you buy a new card of different types to directly to theSCSI disk received a new card, not directly to the old cardpulled out after the new card. There will be a blue screen 2k/xpsystem will crash off. Unless it is to reinstall the system.The most convenient way is that the old system is fixed to theold card, the new card plug into the system, such as drivingsystem recognized the newSCSI card, and then shut down the SCSIline to pull the old new card, SCSI card, so you do not needto reinstall the system and upgrade to the new SCSI card!Several major SCSI driver download connections:

A. teram dc390u3d lsi53c1010-33 Tekram dual channel 160 card/lsi895u3/lsi53c1010-66:http://support.megaraid.com/support/dlcenter1/w2k1010.zip (2k)