重新编译FreeBSD 5.3内核开启SMP/HTT、QUOTA等功能
忙了好多天，Build了不下10遍内核，终于有成果了。
－－－－－－－－－－－－－－－－－－－－
与Linux内核为性能做优化不同，FreeBSD的内核是为稳定性做的优化，而且支持的设备上有所保留。所以使用FreeBSD通常意味着需要自己编译内核，开启诸如SMP/HTT、QUOTA、IPFirewall等功能。同时，也可以将无用的驱动模块去掉，缩小内核体积，进一步提高稳定性和性能。
注：本文仅供参考，具体参数可能根据FreeBSD不同版本而有所不同。
－－－－－－－－－－－－－－－－－－－－－
■■■■编译定制内核■■■■
1) 我们需要使用FreeBSD 5.3 Release的安装光盘装好一个默认的系统，安装时候一定要选择“Kern-Developer”，即安装编译内核所需要的组件。然后选择屏幕最下边的Custom，按空格进入下一层菜单，在里边找到src，按空格进入下一层菜单，选中sys，即安装内核源代码到/usr/src/sys目录下。
2) 使用默认的内核启动系统。备份当前的内核：
cp -R /boot/kernel /boot/kernel.good
这样当新内核出现问题时候，可以随时恢复到原内核。
3) 复制默认内核的配置文件，并且重新命名：
/usr/src/sys/i386/conf
cp GENERIC Prima-Kernel
4) 修改内核配置文件：
vi Prima-Kernel
查找关键字“ident”，并修改如下:
ident Prima-Kernel # set kern's name
为了支持SMP多对称处理器，在文件中加入下内容：
options SMP # Symmetric MultiProcessor Kernel
为了支持HTT超线程，在文件中加入如下内容：
options APIC_IO
注意：Pentium3以后的Xeon都是支持HTT的，所以如果是单路Xeon，则开启HTT；如果是双路Xeon，需要同时开启SMP和HTT。
为了优化网络性能，添加如下参数：
options TCP_DROP_SYNFIN
options ZERO_COPY_SOCKETS
加入Quota磁盘配额的支持：
options QUOTA
5) 编译并安装新内核：
/usr/sbin/config Prima-Kernel
cd ../compile/Prima-Kernel/
make depend
make
make install
注意：整个编译估计需要15分钟左右，根据CPU速度而定。
6) 重新启动系统，默认就会启动新内核。
－－－－－－－－－－－－－－－－－－－－－
■■■■内核升级失败时使用其他内核文件启动■■■■
1) 启动系统时候，出现1到7的选项列表，按下6。
2) 现在进入提示符“OK”状态，可以进行如下操作：
如果需要启动当前系统内核，则输入：
boot kernel
如果需要启动上一个版本的内核，则输入：
boot kernel.old
假如编译新内核前按照本文将原内核备份成了kernel.good，则输入如下内容可以启动这个备份内核：
boot kernel.good
用别的内核启动成功之后，将可以正常使用的内核复制承认默认内核：
rm -rf /boot/kernel
cp -R /boot/kernel.good /boot/kernel
重新启动系统，即可使用原内核正常运行。
－－－－－－－－－－－－－－－－－－－－－
■■■■典型Prima-Kernel内核配置文件■■■■
注意：本配置文件来自FreeBSD 5.3 Release，支持SMP和HTT，仅保留了对Intel板载网卡（em/fxp）以及AIC7xxx SCSI适配器的支持，如果需要支持其他设备，请启用相关配置项。
#
# GENERIC -- Generic kernel configuration file for FreeBSD/i386
#
# For more information on this file, please read the handbook section on
# Kernel Configuration Files:
#
# http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig-config.html
#
# The handbook is also available locally in /usr/share/doc/handbook
# if you've installed the doc distribution, otherwise always see the
# FreeBSD World Wide Web server (http://www.FreeBSD.org/) for the
# latest information.
#
# An exhaustive list of options and more detailed explanations of the
# device lines is also present in the ../../conf/NOTES and NOTES files.
# If you are in doubt as to the purpose or necessity of a line, check first
# in NOTES.
#
# $FreeBSD: src/sys/i386/conf/GENERIC,v 1.413.2.6.2.2 2004/10/24 18:02:52 scottl Exp $
machine i386
#cpu I486_CPU
#cpu I586_CPU
cpu I686_CPU
ident Prima-Kernel
# To statically compile in device wiring instead of /boot/device.hints
#hints "GENERIC.hints" # Default places to look for devices.
options SCHED_4BSD # 4BSD scheduler
options INET # InterNETworking
#options INET6 # IPv6 communications protocols
options FFS # Berkeley Fast Filesystem
options SOFTUPDATES # Enable FFS soft updates support
options UFS_ACL # Support for access control lists
options UFS_DIRHASH # Improve performance on big directories
options MD_ROOT # MD is a potential root device
#options NFSCLIENT # Network Filesystem Client
#options NFSSERVER # Network Filesystem Server
#options NFS_ROOT # NFS usable as /, requires NFSCLIENT
#options MSDOSFS # MSDOS Filesystem
options CD9660 # ISO 9660 Filesystem
options PROCFS # Process filesystem (requires PSEUDOFS)
options PSEUDOFS # Pseudo-filesystem framework
options GEOM_GPT # GUID Partition Tables.
options COMPAT_43 # Compatible with BSD 4.3 [KEEP THIS!]
options COMPAT_FREEBSD4 # Compatible with FreeBSD4
options SCSI_DELAY=5000 # Delay (in ms) before probing SCSI
options KTRACE # ktrace(1) support
options SYSVSHM # SYSV-style shared memory
options SYSVMSG # SYSV-style message queues
options SYSVSEM # SYSV-style semaphores
options _KPOSIX_PRIORITY_SCHEDULING # POSIX P1003_1B real-time extensions
options KBD_INSTALL_CDEV # install a CDEV entry in /dev
options AHC_REG_PRETTY_PRINT # Print register bitfields in debug
# output. Adds ~128k to driver.
options AHD_REG_PRETTY_PRINT # Print register bitfields in debug
# output. Adds ~215k to driver.
options ADAPTIVE_GIANT # Giant mutex is adaptive.
device apic # I/O APIC
options SMP
options APIC_IO
options QUOTA
options TCP_DROP_SYNFIN
options ZERO_COPY_SOCKETS
# Bus support. Do not remove isa, even if you have no isa slots
device isa
device eisa
device pci
# Floppy drives
#device fdc
# ATA and ATAPI devices
device ata
#device atadisk # ATA disk drives
#device ataraid # ATA RAID drives
device atapicd # ATAPI CDROM drives
#device atapifd # ATAPI floppy drives
#device atapist # ATAPI tape drives
options ATA_STATIC_ID # Static device numbering
# SCSI Controllers
#device ahb # EISA AHA1742 family
device ahc # AHA2940 and onboard AIC7xxx devices
#device ahd # AHA39320/29320 and onboard AIC79xx devices
#device amd # AMD 53C974 (Tekram DC-390(T))
#device isp # Qlogic family
#device mpt # LSI-Logic MPT-Fusion
#device ncr # NCR/Symbios Logic
#device sym # NCR/Symbios Logic (newer chipsets + those of `ncr')
#device trm # Tekram DC395U/UW/F DC315U adapters
#device adv # Advansys SCSI adapters
#sdevice adw # Advansys wide SCSI adapters
#device aha # Adaptec 154x SCSI adapters
#device aic # Adaptec 15[012]x SCSI adapters, AIC-6[23]60.
#device bt # Buslogic/Mylex MultiMaster SCSI adapters
#device ncv # NCR 53C500
#device nsp # Workbit Ninja SCSI-3
#device stg # TMC 18C30/18C50
# SCSI peripherals
device scbus # SCSI bus (required for SCSI)
device ch # SCSI media changers
device da # Direct Access (disks)
device sa # Sequential Access (tape etc)
device cd # CD
device pass # Passthrough device (direct SCSI access)
device ses # SCSI Environmental Services (and SAF-TE)
# RAID controllers interfaced to the SCSI subsystem
#device amr # AMI MegaRAID
#device asr # DPT SmartRAID V, VI and Adaptec SCSI RAID
#device ciss # Compaq Smart RAID 5*
#device dpt # DPT Smartcache III, IV - See NOTES for options
#device hptmv # Highpoint RocketRAID 182x
#device iir # Intel Integrated RAID
#device ips # IBM (Adaptec) ServeRAID
#device mly # Mylex AcceleRAID/eXtremeRAID
#device twa # 3ware 9000 series PATA/SATA RAID
# RAID controllers
#device aac # Adaptec FSA RAID
#device aacp # SCSI passthrough for aac (requires CAM)
#device ida # Compaq Smart RAID
#device mlx # Mylex DAC960 family
#device pst # Promise Supertrak SX6000
#device twe # 3ware ATA RAID
# atkbdc0 controls both the keyboard and the PS/2 mouse
device atkbdc # AT keyboard controller
device atkbd # AT keyboard
#device psm # PS/2 mouse
device vga # VGA video card driver
#device splash # Splash screen and screen saver support
# syscons is the default console driver, resembling an SCO console
device sc
# Enable this for the pcvt (VT220 compatible) console driver
#device vt
#options XSERVER # support for X server on a vt console
#options FAT_CURSOR # start with block cursor
device agp # support several AGP chipsets
# Floating point support - do not disable.
device npx
# Power management support (see NOTES for more options)
#device apm
# Add suspend/resume support for the i8254.
device pmtimer
# PCCARD (PCMCIA) support
# PCMCIA and cardbus bridge support
#device cbb # cardbus (yenta) bridge
#device pccard # PC Card (16-bit) bus
#device cardbus # CardBus (32-bit) bus
# Serial (COM) ports
#device sio # 8250, 16[45]50 based serial ports
# Parallel port
#device ppc
#device ppbus # Parallel port bus (required)
#device lpt # Printer
#device plip # TCP/IP over parallel
#device ppi # Parallel port interface device
#device vpo # Requires scbus and da
# If you've got a "dumb" serial or parallel PCI card that is
# supported by the puc(4) glue driver, uncomment the following
# line to enable it (connects to the sio and/or ppc drivers):
#device puc
# PCI Ethernet NICs.
#device de # DEC/Intel DC21x4x (``Tulip'')
#device em # Intel PRO/1000 adapter Gigabit Ethernet Card
#device ixgb # Intel PRO/10GbE Ethernet Card
#device txp # 3Com 3cR990 (``Typhoon'')
#device vx # 3Com 3c590, 3c595 (``Vortex'')
# PCI Ethernet NICs that use the common MII bus controller code.
# NOTE: Be sure to keep the 'device miibus' line in order to use these NICs!
device miibus # MII bus support
#device bfe # Broadcom BCM440x 10/100 Ethernet
#device bge # Broadcom BCM570xx Gigabit Ethernet
#device dc # DEC/Intel 21143 and various workalikes
device fxp # Intel EtherExpress PRO/100B (82557, 82558)
#device lge # Level 1 LXT1001 gigabit ethernet
#device nge # NatSemi DP83820 gigabit ethernet
#device pcn # AMD Am79C97x PCI 10/100 (precedence over 'lnc')
#device re # RealTek 8139C+/8169/8169S/8110S
#device rl # RealTek 8129/8139
#device sf # Adaptec AIC-6915 (``Starfire'')
#device sis # Silicon Integrated Systems SiS 900/SiS 7016
#device sk # SysKonnect SK-984x & SK-982x gigabit Ethernet
#device ste # Sundance ST201 (D-Link DFE-550TX)
#device ti # Alteon Networks Tigon I/II gigabit Ethernet
#device tl # Texas Instruments ThunderLAN
#device tx # SMC EtherPower II (83c170 ``EPIC'')
#device vge # VIA VT612x gigabit ethernet
#device vr # VIA Rhine, Rhine II
#device wb # Winbond W89C840F
#device xl # 3Com 3c90x (``Boomerang'', ``Cyclone'')
# ISA Ethernet NICs. pccard NICs included.
#device cs # Crystal Semiconductor CS89x0 NIC
# 'device ed' requires 'device miibus'
#device ed # NE[12]000, SMC Ultra, 3c503, DS8390 cards
#device ex # Intel EtherExpress Pro/10 and Pro/10+
#device ep # Etherlink III based cards
#device fe # Fujitsu MB8696x based cards
#device ie # EtherExpress 8/16, 3C507, StarLAN 10 etc.
#device lnc # NE2100, NE32-VL Lance Ethernet cards
#device sn # SMC's 9000 series of Ethernet chips
#device xe # Xircom pccard Ethernet
# ISA devices that use the old ISA shims
#device le
# Wireless NIC cards
#device wlan # 802.11 support
#device an # Aironet 4500/4800 802.11 wireless NICs.
#device awi # BayStack 660 and others
#device wi # WaveLAN/Intersil/Symbol 802.11 wireless NICs.
#device wl # Older non 802.11 Wavelan wireless NIC.
# Pseudo devices.
device loop # Network loopback
device mem # Memory and kernel memory devices
device io # I/O device
device random # Entropy device
device ether # Ethernet support
#device sl # Kernel SLIP
#device ppp # Kernel PPP
#device tun # Packet tunnel.
device pty # Pseudo-ttys (telnet etc)
#device md # Memory "disks"
#device gif # IPv6 and IPv4 tunneling
#device faith # IPv6-to-IPv4 relaying (translation)
# The `bpf' device enables the Berkeley Packet Filter.
# Be aware of the administrative consequences of enabling this!
device bpf # Berkeley packet filter
# USB support
#device uhci # UHCI PCI->USB interface
#device ohci # OHCI PCI->USB interface
#device usb # USB Bus (required)
#device udbp # USB Double Bulk Pipe devices
#device ugen # Generic
#device uhid # "Human Interface Devices"
#device ukbd # Keyboard
#device ulpt # Printer
#device umass # Disks/Mass storage - Requires scbus and da
#device ums # Mouse
#device urio # Diamond Rio 500 MP3 player
#device uscanner # Scanners
# USB Ethernet, requires mii
#device aue # ADMtek USB Ethernet
#device axe # ASIX Electronics USB Ethernet
#device cue # CATC USB Ethernet
#device kue # Kawasaki LSI USB Ethernet
#device rue # RealTek RTL8150 USB Ethernet
# FireWire support
#device firewire # FireWire bus code
#device sbp # SCSI over FireWire (Requires scbus and da)
#device fwe # Ethernet over FireWire (non-standard!)注意：内核文件中的注释说，“Do not remove isa, even if you have no isa slots”，即使没有ISA，也不能去掉ISA支持。我就是犯了这个错误，编译完就崩溃N次。。