Storage, computing and distributed computing (collection and sorting is suitable for Xiaobai)

• Server availability
  • BMC Integrated management module （iBMC） Be able to continuously monitor system parameters 、 Trigger alarm , And take recovery measures , In order to avoid downtime to the greatest extent
• Memory module type
  • RDIMM
    Dual in line memory module with registers ,RDIM A register is added to the memory module for transmission , It is located in CPU And memory particles , Because of the high efficiency of registers , So the capacity and frequency are easier to improve ; Maximum capacity ：32G, The frequency is the highest ：3200MT/s
  • UDIMM
    Unbuffered dual inline memory module , Its address and control signals do not pass through the buffer , Directly to DIMM Upper DRAM chip , So the delay is smaller at the same frequency , And because of the manufacturing process , therefore UDIM Low capacity and frequency ; Maximum capacity 4G, The frequency is the highest ：2133MT/s
  • LRDIMM
    Low load dual in line memory module , Simple buffer , Buffering reduces the power load on the lower motherboard , No effect on performance , Reduced memory bus load , Further improve the memory support capacity ; Maximum capacity ：64G, frequency ：3200MT/s
• Hard disk interface type
  • SAS
    Serial connection SCSI, Enterprise application disk , The fastest mechanical hard disk ,SAS Hard disk compatible SATA Interface ,SAS Hard disk pays more attention to reliability ,10000/15000RPM（ turn / branch ）, Transmission rate 300MB/s, In general, it is based on 600G To calculate the storage capacity （ Non written ）
  • SATA
    SATA Serial hard disk , For ordinary users , It is the mainstream of computer mechanical hard disk ,SATA Hard disk is not compatible SAS Interface ,SATA Hard disk tends to be cheap and high-capacity ,7200RPM（ turn / branch ）, The transmission rate is 150MB/S, In general, it is based on 200G To calculate the capacity （ Non written ）
  • NVMe
    Use NVMe Protocol SSD ,NVme Protocol nonvolatile memory host controller interface , Is a logical interface specification ; The transmission rate is 600MB/s, In general, it is based on 960G To calculate the capacity （ Non written ）
  • RAID
    Redundant array of independent disks
    • Raid0
      At least two hard disks are required , Split the data into two hard disks , Read at the same time when reading , Write while writing , Improve the continuous reading and writing ability of the disk , When one of the disks is damaged , Data loss
      ​ Calculation formula ：N Fast disk composition , The logical capacity is N Sum of disk capacity
    • Raid1
      At least two hard disks are required , Copy a complete data to two hard disks , This array is the safest , Space utilization and speed are the lowest
      Calculation formula ： Two disks make up , The logical capacity is N Half of the sum of block disk capacity
    • Raid5
      You need at least three hard drives , Each hard disk stores a part of the recovery code , The disaster tolerance capability of disk is increased , In performance with raid0 near , Disaster tolerance capability is a disk
      Calculation formula ：N It's made up of blocks , The logical capacity is N-1 The sum of the capacities of the disks
    • Raid6
      At least four hard drives are required , And raid5 identical , Each disk stores two copies of the recovery code , The disaster tolerance ability has been improved from one to two hard disks
      Calculation formula ：N Fast disk composition , The logical capacity is N-2 The sum of the capacities of the disks
    • Raid50
      Need at least 9 Block disk , First, make the disk into three pieces Raid5, Then three more Raid5 Combine into one Raid0, It has higher disaster tolerance capability
      Calculation formula ： If each RAID5 from N It's made up of blocks , share M individual RAID5 Make up the RAID50, Then the logical capacity is (N-1)*M Sum of disk capacity .
    • Raid60
      Need at least 8 Block hard disk , Every four hard disks are combined into two Raid6, Two more Raid6 Form a Raid0, It has higher disaster tolerance ability , And higher reading and writing speed , The disaster tolerance capacity is two hard disks
      Calculation formula ： Fake each RAID6 from N It's made up of blocks , share M individual RAID6 Make up the RAID60, Then the logical capacity is (N-2)*M Sum of disk capacity .
    • Raid-tp
      stay raid6 The reliability and safety are increased on the basis of , Every CKG（ Logical block group ） The verification data in occupies three CHUNK（ Logic block ） Space , Allow any three data CHUNK（ Logic block ） fault . If there are four or more CHUNK（ Logic block ） Simultaneous failure , Then the whole RAID Level failure
  • LUN virtualization
    LUN Virtualization can integrate multiple Raid Groups are divided into logical units , And mapped to multiple hosts ,LUN Virtualization can achieve cross Raid Group
  • Block virtualization （Raid2.0）
    Cut the hard disk into multiple logical blocks , Then the logic blocks are composed LUN（ Each logical block comes from a different hard disk ）, be based on LUN do Raid Group , each LUN It's just one. Raid Group
  • The upper LUN virtualization + Bottom block virtualization （Raid2.0+）
    Divide the hard disk into several logical blocks of the same size （chunk）：CK It's usually 64M, Some of them are hot spare blocks ; The rest of the logic blocks are data blocks , The hard disk domain only supports the same type of hard disk. Each hard disk has a part of data blocks combined into a data block group, which is also called a logical block group (chunk group)：CKG, From different hard drives , Then quickly group the data Raid, then Raid Group progress LUN Virtualization is also known as EXCENT：EXCENT It's usually 4MB
  • Raid2.0+ Fast refactoring
    because Raid2.0+ characteristic , After a single hard disk fails , Will be idle CKG Medium CK Traditional reconstruction time used to reconstruct fault data ：30M/s;Raid2.0+ Fast refactoring time ：600M/s, If the fault disk is allocated CK Less , Refactoring is faster
• The Internet
  • Ethernet cable
    The transmission distance of the network cable cannot exceed 100 rice , Effective transmission distance 90 rice , Maximum through repeater 500 rice
    • GE Electric port
      10 Gigabit network cable interface
    • Five category
      Class V network cable 100Mbps( Hundred trillion ) Transmission rate ,CAT.5
    • Super five categories
      Super class 5 network cable barely supports 1000Mbps Transmission rate ,CAT.5e
    • Six categories
      Category VI network cable 250Mhz Transmission frequency 1000Mbps（ Gigabit ） Transmission rate ,CAT.6
    • Super six categories
      Cat 6 network cable 500Mhz Transmission frequency ,1000Mbps（ Gigabit ） Transmission rate ,CAT.6a
    • Seven category
      Class VII network cable 500Mhz Transmission frequency ,10Gbps（ Ten thousand trillion ） Transmission rate ,CAT.7
  • Optical fiber
    • GE Smooth mouth
      10 Gigabit fiber interface
    • Fiber optic interface
      • FC type
      • SC type
      • LC type
      • ST type
    • Optical module package type
      SFP、XFP、XENPAK、BIDI SFP、GBIC、ESFP（ common SFP、SFP+、QSFP、QSFP+）
      • SFP
        Small pluggable optical module , The maximum transmission rate shall not exceed 5Gbps within
      • SFP+
        Enhanced SFP modular , The transmission rate is 10Gbps
      • QSFP
        Four channel small pluggable module , The transmission rate is 5Gbps
      • QSFP+
        Enhanced four channel small pluggable module , The transmission rate is 40Gbps
    • Optical module
      • Monomode SM
        1310nm, Large transmission loss , But the dispersion is small , Generally used in 40KM Transmission within
        1550nm, Low transmission loss , But the dispersion is large , Generally used in 40KM Transmission beyond
      • multimode MM
        850nm, Low cost, short transmission distance , Generally only support 500M
      • CWDM
        A low-cost solution for metropolitan area network access layer WDM Transmission technology , It is mainly used in Enterprise Networks , Campus network
      • DWDM
        A laser technology used to improve the bandwidth of the existing optical backbone network , Long distance trunk network , Core node of large capacity metropolitan area network
• PCIe
  High speed serial computer extended bus standard
  • PCIe edition
    Different versions PCIe The version transfer rate is different
    • 1.0
      Transmission rate ：2.5GT/s
    • 2.0
      Transmission rate ：5GT/s
    • 3.0
      Transmission rate ：8GT/s
    • 4.0
      Transmission rate ：16GT/s
    • 5.0
      Transmission rate ：32GT/s
  • PCIe Interface classification
    • x16
      Universal slot , Usually a graphics card or AI Accelerator card ,AI Reasoning cards and Raid Display cards, etc
    • x8
      Usually processed as X16 The style of , But only half of the stitches are effective , For graphics card or AI Accelerator card ,AI Reasoning cards and Raid Display card
    • x4
      Usually solid state disk interface
    • x1
      Usually independent network card , Independent sound card ,USB3.0 Expansion card
• Power Supply
  • AC
    Alternating current (ac)
  • DC
    Direct current