Latest working kernel version: unknown Earliest failing kernel version: detected on kernel-2.6.25 Distribution: gentoo Hardware Environment: Asus A7A266 motherboard with BIOS upgraded to latest release (no beta version of upgrade) lspci output: 00:00.0 Host bridge: ALi Corporation M1647 Northbridge [MAGiK 1 / MobileMAGiK 1] (rev 04) 00:01.0 PCI bridge: ALi Corporation PCI to AGP Controller 00:02.0 USB Controller: ALi Corporation USB 1.1 Controller (rev 03) 00:04.0 IDE interface: ALi Corporation M5229 IDE (rev c4) 00:05.0 Multimedia audio controller: C-Media Electronics Inc CM8738 (rev 10) 00:06.0 USB Controller: ALi Corporation USB 1.1 Controller (rev 03) 00:07.0 ISA bridge: ALi Corporation M1533/M1535 PCI to ISA Bridge [Aladdin IV/V/V+] 00:0a.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10) 00:0c.0 Serial controller: Rockwell International HCF 56k Data/Fax Modem (rev 01) 00:11.0 Bridge: ALi Corporation M7101 Power Management Controller [PMU] 01:00.0 VGA compatible controller: nVidia Corporation NV4 [RIVA TNT] (rev 04) Software Environment: Gentoo Linux. Problem Description: Hdd is slow and dmesg show a strange message Steps to reproduce:compile kernel and boot Output of script/ver_linux If some fields are empty or look unusual you may have an old version. Compare to the current minimal requirements in Documentation/Changes. Linux AServer 2.6.26.1 #1 Wed Sep 24 00:18:06 CEST 2008 i686 AMD Athlon(TM) XP1600+ AuthenticAMD GNU/Linux Gnu C 4.1.2 Gnu make 3.81 binutils 2.18 util-linux 2.13.1.1 mount 2.13.1.1 module-init-tools 3.4 e2fsprogs 1.40.9 reiserfsprogs 3.6.19 Linux C Library 2.6.1 Dynamic linker (ldd) 2.6.1 Procps 3.2.7 Net-tools 1.60 Kbd 1.13 Sh-utils 6.9 udev 124 Modules Loaded ipt_REJECT ipt_LOG ipt_addrtype xt_pkttype xt_multiport xt_MARK xt_mac xt_iprange xt_tcpudp xt_state nf_conntrack_ipv4 nf_conntrack iptable_mangle nfnetlink iptable_filter ip_tables x_tables ohci_hcd usbcore i2c_ali1535 dmesg output: ide0 at 0x1f0-0x1f7,0x3f6 on irq 14 ide1 at 0x170-0x177,0x376 on irq 15 hda: max request size: 128KiB hda: cannot use LBA48 DMA - PIO mode will be used for accessing sectors > 268435456 hda: 488397168 sectors (250059 MB) w/8192KiB Cache, CHS=30401/255/63 hda: cache flushes supported hda: hda1 hda2 hda3 hda4 hdc: max request size: 128KiB hdc: cannot use LBA48 DMA - PIO mode will be used for accessing sectors > 268435456 hdc: 488397168 sectors (250059 MB) w/8192KiB Cache, CHS=30401/255/63 hdparm output: hdparm -Tt /dev/hdc output: /dev/hdc: Timing cached reads: 388 MB in 2.01 seconds = 193.07 MB/sec Timing buffered disk reads: 142 MB in 3.03 seconds = 46.89 MB/sec (I want to get something above 500MB/sec) May it help (googled) i found that related info: https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/119730 http://osdir.com/ml/ide/2005-03/msg00064.html
(In reply to comment #0) > hdc: cannot use LBA48 DMA - PIO mode will be used for accessing sectors > > 268435456 The IDE core honestly warns you that the controller doesn't support DMA for accesses abobe 137 GB. Where's the problem? > hdc: 488397168 sectors (250059 MB) w/8192KiB Cache, CHS=30401/255/63 > hdparm output: > hdparm -Tt /dev/hdc output: > /dev/hdc: > Timing cached reads: 388 MB in 2.01 seconds = 193.07 MB/sec > Timing buffered disk reads: 142 MB in 3.03 seconds = 46.89 MB/sec > (I want to get something above 500MB/sec) 500 MB/s on disk reads?! That's totally wrong expectaion. What I am seeing seems quite adequate speed for UltraDMA. And cached reads don't measure disk transfer speed but rather your CPU bus/memory bandwidth. > May it help (googled) > i found that related info: > https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/119730 > http://osdir.com/ml/ide/2005-03/msg00064.html The latter reports DMA timeouts -- now that's an error indeed. But the report is against 2.6.11. :-) I suggest this to be resolved INVALID.
This is a hardware limit.
> 500 MB/s on disk reads?! That's totally wrong expectaion For my personal computer (Pentium IV) hdparm -Tt /dev/hda /dev/hda: Timing cached reads: 1500 MB in 2.00 seconds = 749.31 MB/sec Timing buffered disk reads: 184 MB in 3.01 seconds = 61.14 MB/sec Server I'm using its athlon 1800MHz and I got same performance as previous server I got (k6-II @ 450MHz) I found server slow in transfers and high CPU usage (and k6-II never warnning me for hardware limits :S) This is the reason I'm in doubt. Upgrading server didn't increase transfers between my PC and my server, in my local network :( Thanks for replies.
> Timing buffered disk reads: 184 MB in 3.01 seconds = 61.14 MB/sec is the disk speed