READAHEAD

From: age (ahuisman_at_cistron.nl)
Date: 10/30/03

  • Next message: Xose Vazquez Perez: "[PATCH] 2.4.23-pre9 fix for kbuild - hotplug_acpi"
    Date:	Thu, 30 Oct 2003 20:23:06 +0100
    To: linux-kernel@vger.kernel.org
    
    

    Hi, Andre

    Hi,

    I have a problem which i don`t understand and i hope that you
    will and can help me. The problem is that i experience strange disk
    read performance. I have to set hdparm -m16 -u1 -c1 -d1 -a4096 /dev/hde
    to get timing buffered disk reads of 56 MB/SEC.
    When i disable readahead i get 17 MB/SEC
    When i enable readahead with -a8 i get 17 MB/SEC
    When i enable readahead with -a16 i get 24,5 MB/SEC
    When i enable readahead with -a32 i get 30,5 MB/SEC
    When i enable readahead with -a64 i get 35 MB/SEC
    When i enable readahead with -a128 i get 39 MB/SEC
    When i enable readahead with -a256 i get 39 MB/SEC
    When i enable readahead with -a512 i get 41 MB/SEC
    When i enable readahead with -a1024 i get 50 MB/SEC
    When i enable readahead with -a2048 i get 50 MB/SEC
    When i enable readahead with -a4096 i get 56 MB/SEC
    With -a8192,-a16384 and -a32768 i get also 56MB/SEC

    Before, i never had to set readahead so high
    Please could you tell me, what is going on here ?

    I use 2.6.0-test9 with TCQ enabled.
    The harddisk is the new Hitachi 7K250 40 GB PATA.

    PS: It doesn`t matter when i disable tcq and/or multcount, i get
          the same results.

    THX

    Age huisman

    /dev/hde:

    Model=HDS722540VLAT20, FwRev=V31OA60A, SerialNo=VN321EC2R9X1ML
    Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs }
    RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=52
    BuffType=DualPortCache, BuffSize=1794kB, MaxMultSect=16, MultSect=16
    CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=80418240
    IORDY=on/off, tPIO={min:240,w/IORDY:120}, tDMA={min:120,rec:120}
    PIO modes: pio0 pio1 pio2 pio3 pio4
    DMA modes: mdma0 mdma1 mdma2
    UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5
    AdvancedPM=yes: disabled (255) WriteCache=enabled
    Drive conforms to: ATA/ATAPI-6 T13 1410D revision 3a:

    * signifies the current active mode

    ATA device, with non-removable media
    powers-up in standby; SET FEATURES subcmd spins-up.
            Model Number: HDS722540VLAT20
            Serial Number: VN321EC2R9X1ML
            Firmware Revision: V31OA60A
    Standards:
            Used: ATA/ATAPI-6 T13 1410D revision 3a
            Supported: 6 5 4 3
    Configuration:
            Logical max current
            cylinders 16383 65535
            heads 16 1
            sectors/track 63 63
            --
            CHS current addressable sectors: 4128705
            LBA user addressable sectors: 80418240
            LBA48 user addressable sectors: 80418240
            device size with M = 1024*1024: 39266 MBytes
            device size with M = 1000*1000: 41174 MBytes (41 GB)
    Capabilities:
            LBA, IORDY(can be disabled)
            bytes avail on r/w long: 52 Queue depth: 32
            Standby timer values: spec'd by Standard, no device specific minimum
            R/W multiple sector transfer: Max = 16 Current = 16
            Advanced power management level: unknown setting (0x0000)
            Recommended acoustic management value: 128, current value: 254
            DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5
                 Cycle time: min=120ns recommended=120ns
            PIO: pio0 pio1 pio2 pio3 pio4
                 Cycle time: no flow control=240ns IORDY flow control=120ns
    Commands/features:
            Enabled Supported:
               * NOP cmd
               * READ BUFFER cmd
               * WRITE BUFFER cmd
               * Host Protected Area feature set
                    Release interrupt
               * Look-ahead
               * Write cache
               * Power Management feature set
                    Security Mode feature set
                    SMART feature set
               * FLUSH CACHE EXT command
               * Mandatory FLUSH CACHE command
               * Device Configuration Overlay feature set
               * 48-bit Address feature set
                    Automatic Acoustic Management feature set
                    SET MAX security extension
                    Address Offset Reserved Area Boot
                    SET FEATURES subcommand required to spinup after power up
                    Power-Up In Standby feature set
                    Advanced Power Management feature set
               * READ/WRITE DMA QUEUED
               * General Purpose Logging feature set
               * SMART self-test
               * SMART error logging
    Security:
            Master password revision code = 65534
                    supported
            not enabled
            not locked
            not frozen
            not expired: security count
            not supported: enhanced erase
            22min for SECURITY ERASE UNIT.
    HW reset results:
            CBLID- above Vih
            Device num = 0 determined by the jumper
    Checksum: correct

    00:0e.0 Unknown mass storage controller: Promise Technology, Inc. 20269 (rev
    02) (prog-if 85)
            Subsystem: Promise Technology, Inc. Ultra133TX2
            Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
    Stepping- SERR- FastB2B-
            Status: Cap+ 66Mhz+ UDF- FastB2B- ParErr- DEVSEL=slow >TAbort-
    <TAbort- <MAbort- >SERR- <PERR-
            Latency: 64 (1000ns min, 4500ns max), Cache Line Size: 0x08 (32
    bytes)
            Interrupt: pin A routed to IRQ 10
            Region 0: I/O ports at eff0 [size=8]
            Region 1: I/O ports at efe4 [size=4]
            Region 2: I/O ports at efa8 [size=8]
            Region 3: I/O ports at efe0 [size=4]
            Region 4: I/O ports at ef90 [size=16]
            Region 5: Memory at febfc000 (32-bit, non-prefetchable) [size=16K]
            Expansion ROM at febf8000 [disabled] [size=16K]
            Capabilities: [60] Power Management version 1
                    Flags: PMEClk- DSI+ D1+ D2- AuxCurrent=0mA
    PME(D0-,D1-,D2-,D3hot-,D3cold-)
                    Status: D0 PME-Enable- DSel=0 DScale=0 PME-

    wuuk:/proc/ide/hde# cat settings
    name value min max mode
    ---- ----- --- --- ----
    acoustic 0 0 254 rw
    address 1 0 2 rw
    bios_cyl 16383 0 65535 rw
    bios_head 255 0 255 rw
    bios_sect 63 0 63 rw
    bswap 0 0 1 r
    current_speed 69 0 70 rw
    failures 0 0 65535 rw
    init_speed 69 0 70 rw
    io_32bit 1 0 3 rw
    keepsettings 0 0 1 rw
    lun 0 0 7 rw
    max_failures 1 0 65535 rw
    multcount 16 0 16 rw
    nice1 1 0 1 rw
    nowerr 0 0 1 rw
    number 0 0 3 rw
    pio_mode write-only 0 255 w
    slow 0 0 1 rw
    unmaskirq 1 0 1 rw
    using_dma 1 0 1 rw
    using_tcq 1 0 32 rw
    wcache 0 0 1 rw

    wuuk:~# dmesg
    Linux version 2.6.0-test9 (root@wuuk) (gcc version 3.3.2 (Debian)) #1
    Wed Oct
    29 02:23:54 CET 2003
    BIOS-provided physical RAM map:
    BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
    BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
    BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
    BIOS-e820: 0000000000100000 - 000000001ffe0000 (usable)
    BIOS-e820: 000000001ffe0000 - 000000001fff8000 (ACPI data)
    BIOS-e820: 000000001fff8000 - 0000000020000000 (ACPI NVS)
    BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved)
    BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
    BIOS-e820: 00000000fff80000 - 0000000100000000 (reserved)
    511MB LOWMEM available.
    On node 0 totalpages: 131040
      DMA zone: 4096 pages, LIFO batch:1
      Normal zone: 126944 pages, LIFO batch:16
      HighMem zone: 0 pages, LIFO batch:1
    DMI 2.1 present.
    Building zonelist for node : 0
    Kernel command line: root=/dev/hde2 ro vga=3845
    Local APIC disabled by BIOS -- reenabling.
    Found and enabled local APIC!
    Initializing CPU#0
    PID hash table entries: 2048 (order 11: 16384 bytes)
    Detected 448.128 MHz processor.
    Console: colour VGA+ 80x30
    Memory: 515404k/524160k available (1814k kernel code, 8004k reserved, 675k
    data, 124k init, 0k highmem)
    Calibrating delay loop... 884.73 BogoMIPS
    Dentry cache hash table entries: 65536 (order: 6, 262144 bytes)
    Inode-cache hash table entries: 32768 (order: 5, 131072 bytes)
    Mount-cache hash table entries: 512 (order: 0, 4096 bytes)
    CPU: After generic identify, caps: 0383fbff 00000000 00000000 00000000
    CPU: After vendor identify, caps: 0383fbff 00000000 00000000 00000000
    CPU: L1 I cache: 16K, L1 D cache: 16K
    CPU: L2 cache: 512K
    CPU: After all inits, caps: 0383fbff 00000000 00000000 00000040
    CPU: Intel Pentium III (Katmai) stepping 03
    Enabling fast FPU save and restore... done.
    Enabling unmasked SIMD FPU exception support... done.
    Checking 'hlt' instruction... OK.
    POSIX conformance testing by UNIFIX
    enabled ExtINT on CPU#0
    ESR value before enabling vector: 00000000
    ESR value after enabling vector: 00000000
    Using local APIC timer interrupts.
    calibrating APIC timer ...
    ..... CPU clock speed is 447.0981 MHz.
    ..... host bus clock speed is 99.0551 MHz.
    NET: Registered protocol family 16
    PCI: PCI BIOS revision 2.10 entry at 0xfdb91, last bus=1
    PCI: Using configuration type 1
    mtrr: v2.0 (20020519)
    drivers/usb/core/usb.c: registered new driver hub
    PCI: Probing PCI hardware
    PCI: Probing PCI hardware (bus 00)
    PCI: Using IRQ router PIIX [8086/7110] at 0000:00:07.0
    IA-32 Microcode Update Driver: v1.13 <tigran@veritas.com>
    Limiting direct PCI/PCI transfers.
    pty: 256 Unix98 ptys configured
    Real Time Clock Driver v1.12
    Linux agpgart interface v0.100 (c) Dave Jones
    agpgart: Detected an Intel 440BX Chipset.
    agpgart: Maximum main memory to use for agp memory: 439M
    agpgart: AGP aperture is 64M @ 0xf8000000
    Using anticipatory io scheduler
    Floppy drive(s): fd0 is 1.44M
    floppy0: no floppy controllers found
    RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
    loop: loaded (max 8 devices)
    8139too Fast Ethernet driver 0.9.26
    PCI: Found IRQ 5 for device 0000:00:0f.0
    eth0: RealTek RTL8139 at 0xe0823c00, 00:02:44:47:f8:69, IRQ 5
    eth0: Identified 8139 chip type 'RTL-8100B/8139D'
    Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
    ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
    PIIX4: IDE controller at PCI slot 0000:00:07.1
    PIIX4: chipset revision 1
    PIIX4: not 100% native mode: will probe irqs later
        ide1: BM-DMA at 0xffa8-0xffaf, BIOS settings: hdc:DMA, hdd:pio
    hdc: JLMS XJ-HD166S, ATAPI CD/DVD-ROM drive
    ide1 at 0x170-0x177,0x376 on irq 15
    PDC20269: IDE controller at PCI slot 0000:00:0e.0
    PCI: Found IRQ 10 for device 0000:00:0e.0
    PDC20269: chipset revision 2
    PDC20269: ROM enabled at 0xfebf8000
    PDC20269: 100% native mode on irq 10
        ide2: BM-DMA at 0xef90-0xef97, BIOS settings: hde:pio, hdf:pio
        ide3: BM-DMA at 0xef98-0xef9f, BIOS settings: hdg:pio, hdh:pio
    hde: HDS722540VLAT20, ATA DISK drive
    ide2 at 0xeff0-0xeff7,0xefe6 on irq 10
    hde: max request size: 1024KiB
    hde: 80418240 sectors (41174 MB) w/1794KiB Cache, CHS=16383/255/63,
    UDMA(100)
    hde: tagged command queueing enabled, command queue depth 32
    hde: hde1 hde2 hde3
    end_request: I/O error, dev hdc, sector 0
    hdc: ATAPI 48X DVD-ROM drive, 512kB Cache, UDMA(33)
    Uniform CD-ROM driver Revision: 3.12
    ide-floppy driver 0.99.newide
    drivers/usb/host/uhci-hcd.c: USB Universal Host Controller Interface driver
    v2.1
    PCI: Found IRQ 9 for device 0000:00:07.2
    uhci_hcd 0000:00:07.2: UHCI Host Controller
    uhci_hcd 0000:00:07.2: irq 9, io base 0000ef40
    uhci_hcd 0000:00:07.2: new USB bus registered, assigned bus number 1
    hub 1-0:1.0: USB hub found
    hub 1-0:1.0: 2 ports detected
    drivers/usb/core/usb.c: registered new driver hiddev
    drivers/usb/core/usb.c: registered new driver hid
    drivers/usb/input/hid-core.c: v2.0:USB HID core driver
    mice: PS/2 mouse device common for all mice
    serio: i8042 AUX port at 0x60,0x64 irq 12
    input: AT Translated Set 2 keyboard on isa0060/serio0
    serio: i8042 KBD port at 0x60,0x64 irq 1
    NET: Registered protocol family 2
    IP: routing cache hash table of 4096 buckets, 32Kbytes
    TCP: Hash tables configured (established 32768 bind 65536)
    NET: Registered protocol family 1
    NET: Registered protocol family 17
    NET: Registered protocol family 15
    BIOS EDD facility v0.10 2003-Oct-11, 1 devices found
    Please report your BIOS at http://domsch.com/linux/edd30/results.html
    kjournald starting. Commit interval 5 seconds
    EXT3-fs: mounted filesystem with ordered data mode.
    VFS: Mounted root (ext3 filesystem) readonly.
    Freeing unused kernel memory: 124k freed
    hub 1-0:1.0: new USB device on port 1, assigned address 2
    input: USB HID v1.10 Mouse [Logitech USB Mouse] on usb-0000:00:07.2-1
    Adding 124952k swap on /dev/hde1. Priority:-1 extents:1
    EXT3 FS on hde2, internal journal
    eth0: link up, 100Mbps, full-duplex, lpa 0x45E1
    Serial: 8250/16550 driver $Revision: 1.90 $ 8 ports, IRQ sharing disabled
    ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
    ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
    microcode: CPU0 updated from revision 0xa to 0xe, date = 09101999

    /dev/hde:
    multcount = 16 (on)
    IO_support = 1 (32-bit)
    unmaskirq = 1 (on)
    using_dma = 1 (on)
    keepsettings = 0 (off)
    readonly = 0 (off)
    readahead = 4096 (on)
    geometry = 16383/255/63, sectors = 80418240, start = 0

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  • Next message: Xose Vazquez Perez: "[PATCH] 2.4.23-pre9 fix for kbuild - hotplug_acpi"