Hello I'm seeing very slow writes on a Dell Precision 690 with the Dell SAS5 adapter, serving a RAID1 array of SATA-II disks. It's very similar to the problem in FreeBSD, described here: http://unix.derkeiler.com/Mailing-Lists/FreeBSD/stable/2007-03/msg00756.html I'm running FC6 with the latest kernel. Reads are quite fast, writes terribly slow. dmesg and lspci out below. Is the Linux driver suffering from a similar problem? Adam SCSI subsystem initialized Fusion MPT base driver 3.04.03 Copyright (c) 1999-2007 LSI Logic Corporation Fusion MPT SAS Host driver 3.04.03 ACPI: PCI Interrupt 0000:05:0b.0[A] -> GSI 24 (level, low) -> IRQ 24 mptbase: Initiating ioc0 bringup ioc0: SAS1068: Capabilities={Initiator} scsi0 : ioc0: LSISAS1068, FwRev=00063200h, Ports=1, MaxQ=511, IRQ=24 scsi 0:0:0:0: Direct-Access ATA WDC WD5000KS-75M 2E08 PQ: 0 ANSI: 5 scsi 0:0:1:0: Direct-Access ATA HDS725050KLA360 AB5A PQ: 0 ANSI: 5 scsi 0:1:0:0: Direct-Access Dell VIRTUAL DISK 1028 PQ: 0 ANSI: 5 SCSI device sda: 976562176 512-byte hdwr sectors (500000 MB) sda: Write Protect is off sda: Mode Sense: 03 00 00 08 SCSI device sda: write cache: disabled, read cache: enabled, doesn't support DPO or FUA SCSI device sda: 976562176 512-byte hdwr sectors (500000 MB) sda: Write Protect is off sda: Mode Sense: 03 00 00 08 SCSI device sda: write cache: disabled, read cache: enabled, doesn't support DPO or FUA sda: sda1 sda2 sda3 sd 0:1:0:0: Attached scsi disk sda There are no cache-related options in the controller BIOS. 00:00.0 Host bridge: Intel Corporation 5000X Chipset Memory Controller Hub (rev 12) 00:02.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 2 (rev 12) 00:03.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 3 (rev 12) 00:04.0 PCI bridge: Intel Corporation 5000X Chipset PCI Express x16 Port 4-7 (rev 12) 00:05.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 5 (rev 12) 00:06.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 6 (rev 12) 00:07.0 PCI bridge: Intel Corporation 5000 Series Chipset PCI Express x4 Port 7 (rev 12) 00:10.0 Host bridge: Intel Corporation 5000 Series Chipset Error Reporting Registers (rev 12) 00:10.1 Host bridge: Intel Corporation 5000 Series Chipset Error Reporting Registers (rev 12) 00:10.2 Host bridge: Intel Corporation 5000 Series Chipset Error Reporting Registers (rev 12) 00:11.0 Host bridge: Intel Corporation 5000 Series Chipset Reserved Registers (rev 12) 00:13.0 Host bridge: Intel Corporation 5000 Series Chipset Reserved Registers (rev 12) 00:15.0 Host bridge: Intel Corporation 5000 Series Chipset FBD Registers (rev 12) 00:16.0 Host bridge: Intel Corporation 5000 Series Chipset FBD Registers (rev 12) 00:1b.0 Audio device: Intel Corporation 631xESB/632xESB High Definition Audio Controller (rev 09) 00:1c.0 PCI bridge: Intel Corporation 631xESB/632xESB/3100 Chipset PCI Express Root Port 1 (rev 09) 00:1d.0 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #1 (rev 09) 00:1d.1 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #2 (rev 09) 00:1d.2 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #3 (rev 09) 00:1d.3 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset UHCI USB Controller #4 (rev 09) 00:1d.7 USB Controller: Intel Corporation 631xESB/632xESB/3100 Chipset EHCI USB2 Controller (rev 09) 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev d9) 00:1f.0 ISA bridge: Intel Corporation 631xESB/632xESB/3100 Chipset LPC Interface Controller (rev 09) 00:1f.1 IDE interface: Intel Corporation 631xESB/632xESB IDE Controller (rev 09) 00:1f.2 SATA controller: Intel Corporation 631xESB/632xESB SATA Storage Controller AHCI (rev 09) 00:1f.3 SMBus: Intel Corporation 631xESB/632xESB/3100 Chipset SMBus Controller (rev 09) 01:00.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Upstream Port (rev 01) 01:00.3 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express to PCI-X Bridge (rev 01) 02:00.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Downstream Port E1 (rev 01) 02:01.0 PCI bridge: Intel Corporation 6311ESB/6321ESB PCI Express Downstream Port E2 (rev 01) 05:0b.0 SCSI storage controller: LSI Logic / Symbios Logic SAS1068 PCI-X Fusion-MPT SAS (rev 01) 07:00.0 VGA compatible controller: nVidia Corporation Quadro FX 3500 (rev a1) 0b:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5752 Gigabit Ethernet PCI Express (rev 02) 0c:0a.0 FireWire (IEEE 1394): Texas Instruments TSB43AB22/A IEEE-1394a-2000 Controller (PHY/Link) - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
