Greetings! I'm using a 2.6.17.4 kernel (straight from kernel.org) patched with libata-tj-stable-2.6.17.4-20060710 in an effort to make use of an external drive bay with a Silicon Image port multipler and a bunch of SATA/PATA drives. For the most part, it's a success (more below) but the write performance that I'm seeing to a new Seagate 750GB drive (with NCQ) is terrible (on the order of 1.2MBytes/sec). The host is an old Toshiba laptop (PIIX4 based) with a 550MHz Celeron processor. The SATA host interface is a PCMCIA based Silicon Image 3124 chip plugged into the Yenta PCMCIA controller. A tulip based Linksys 10/100 card takes up the other slot. From dmesg: ACPI: PCI Interrupt 0000:00:04.1[B] -> Link [LNKB] -> GSI 10 (level, low) -> IRQ 10 Yenta: CardBus bridge found at 0000:00:04.1 [1179:ff00] Yenta: Using CSCINT to route CSC interrupts to PCI Yenta: Routing CardBus interrupts to PCI Yenta TI: socket 0000:00:04.1, mfunc 0x000c1722, devctl 0x66 usb 1-1: configuration #1 chosen from 1 choice Yenta: ISA IRQ mask 0x0838, PCI irq 10 Socket status: 30000020 pccard: CardBus card inserted into slot 0 pccard: CardBus card inserted into slot 1 st: Version 20050830, fixed bufsize 32768, s/g segs 256 Adding 248996k swap on /dev/hda2. Priority:42 extents:1 across:248996k BIOS EDD facility v0.16 2004-Jun-25, 1 devices found Linux Tulip driver version 1.1.13-NAPI (May 11, 2002) PCI: Enabling device 0000:02:00.0 (0000 -> 0003) ACPI: PCI Interrupt 0000:02:00.0[A] -> Link [LNKA] -> GSI 10 (level, low) -> IRQ 10 PCI: Setting latency timer of device 0000:02:00.0 to 64 tulip0: EEPROM default media type Autosense. tulip0: Index #0 - Media MII (#11) described by a 21142 MII PHY (3) block. tulip0: MII transceiver #0 config 3000 status 7829 advertising 01e1. eth0: Digital DS21143 Tulip rev 65 at 00011400, 00:E0:98:04:21:54, IRQ 10. libata version 2.00 loaded. sata_sil24 0000:06:00.0: version 0.3 PCI: Enabling device 0000:06:00.0 (0080 -> 0083) ACPI: PCI Interrupt 0000:06:00.0[A] -> Link [LNKB] -> GSI 10 (level, low) -> IRQ 10 PCI: Setting latency timer of device 0000:06:00.0 to 64 ata1: SATA max UDMA/100 cmd 0xC8CB0000 ctl 0x0 bmdma 0x0 irq 10 ata2: SATA max UDMA/100 cmd 0xC8CB2000 ctl 0x0 bmdma 0x0 irq 10 ata3: SATA max UDMA/100 cmd 0xC8CB4000 ctl 0x0 bmdma 0x0 irq 10 ata4: SATA max UDMA/100 cmd 0xC8CB6000 ctl 0x0 bmdma 0x0 irq 10 scsi0 : sata_sil24 ata1: SATA link down (SStatus 0 SControl 300) scsi1 : sata_sil24 ata2: SATA link down (SStatus 0 SControl 300) scsi2 : sata_sil24 ata3: SATA link down (SStatus 0 SControl 300) scsi3 : sata_sil24 ata4: SATA link down (SStatus 0 SControl 300) The /var/log/messages output after hotplugging the multiplier. Note the NCQ for ata1.00: Aug 27 18:48:26 linux-srv kernel: ata1: soft resetting port Aug 27 18:48:26 linux-srv kernel: ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Aug 27 18:48:26 linux-srv kernel: ata1.15: Port Multiplier 1.1, 0x1095:0x3726 r23, 5 ports, feat 0x9/0x9 Aug 27 18:48:27 linux-srv kernel: ata1.00: hard resetting port Aug 27 18:48:29 linux-srv kernel: ata1.00: SATA link up 1.5 Gbps (SStatus 113 SControl 310) Aug 27 18:48:29 linux-srv kernel: ata1.01: hard resetting port Aug 27 18:48:30 linux-srv kernel: ata1.01: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Aug 27 18:48:30 linux-srv kernel: ata1.02: hard resetting port Aug 27 18:48:31 linux-srv kernel: ata1.02: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Aug 27 18:48:31 linux-srv kernel: ata1.03: hard resetting port Aug 27 18:48:31 linux-srv kernel: ata1.03: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Aug 27 18:48:31 linux-srv kernel: ata1.04: hard resetting port Aug 27 18:48:32 linux-srv kernel: ata1.04: SATA link down (SStatus 0 SControl 300) Aug 27 18:48:32 linux-srv kernel: ata1.00: ATA-7, max UDMA/133, 1465149168 sectors: LBA48 NCQ (depth 31/32) Aug 27 18:48:32 linux-srv kernel: ata1.00: configured for UDMA/100 Aug 27 18:48:32 linux-srv kernel: ata1.01: ATA-7, max UDMA/133, 490234752 sectors: LBA48 Aug 27 18:48:32 linux-srv kernel: ata1.01: ata1: dev 0 multi count 0 Aug 27 18:48:32 linux-srv kernel: ata1.01: applying bridge limits Aug 27 18:48:32 linux-srv kernel: ata1.01: configured for UDMA/100 Aug 27 18:48:32 linux-srv kernel: ata1.02: ATA-6, max UDMA/100, 488397168 sectors: LBA48 Aug 27 18:48:32 linux-srv kernel: ata1.02: ata1: dev 0 multi count 0 Aug 27 18:48:32 linux-srv kernel: ata1.02: applying bridge limits Aug 27 18:48:32 linux-srv kernel: ata1.02: configured for UDMA/100 Aug 27 18:48:32 linux-srv kernel: ata1.03: ATA-6, max UDMA/100, 488397168 sectors: LBA48 Aug 27 18:48:32 linux-srv kernel: ata1.03: ata1: dev 0 multi count 0 Aug 27 18:48:32 linux-srv kernel: ata1.03: applying bridge limits Aug 27 18:48:32 linux-srv kernel: ata1.03: configured for UDMA/100 Aug 27 18:48:32 linux-srv kernel: ata1: EH complete Aug 27 18:48:32 linux-srv kernel: Vendor: ATA Model: ST3750640AS Rev: 3.AA Aug 27 18:48:32 linux-srv kernel: Type: Direct-Access ANSI SCSI revision: 05 Aug 27 18:48:32 linux-srv kernel: SCSI device sda: 1465149168 512-byte hdwr sectors (750156 MB) Aug 27 18:48:32 linux-srv kernel: sda: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sda: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sda: drive cache: write back Aug 27 18:48:32 linux-srv kernel: SCSI device sda: 1465149168 512-byte hdwr sectors (750156 MB) Aug 27 18:48:32 linux-srv kernel: sda: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sda: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sda: drive cache: write back Aug 27 18:48:32 linux-srv kernel: sda: sda1 Aug 27 18:48:32 linux-srv kernel: sd 0:0:0:0: Attached scsi disk sda Aug 27 18:48:32 linux-srv kernel: sd 0:0:0:0: Attached scsi generic sg0 type 0 Aug 27 18:48:32 linux-srv kernel: Vendor: ATA Model: Maxtor 6Y250P0 Rev: YAR4 Aug 27 18:48:32 linux-srv kernel: Type: Direct-Access ANSI SCSI revision: 05 Aug 27 18:48:32 linux-srv kernel: SCSI device sdb: 490234752 512-byte hdwr sectors (251000 MB) Aug 27 18:48:32 linux-srv kernel: sdb: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sdb: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sdb: drive cache: write back Aug 27 18:48:32 linux-srv kernel: SCSI device sdb: 490234752 512-byte hdwr sectors (251000 MB) Aug 27 18:48:32 linux-srv kernel: sdb: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sdb: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sdb: drive cache: write back Aug 27 18:48:32 linux-srv kernel: sdb: sdb1 Aug 27 18:48:32 linux-srv kernel: sd 0:0:1:0: Attached scsi disk sdb Aug 27 18:48:32 linux-srv kernel: sd 0:0:1:0: Attached scsi generic sg1 type 0 Aug 27 18:48:32 linux-srv kernel: Vendor: ATA Model: WDC WD2500BB-00G Rev: 08.0 Aug 27 18:48:32 linux-srv kernel: Type: Direct-Access ANSI SCSI revision: 05 Aug 27 18:48:32 linux-srv kernel: SCSI device sdc: 488397168 512-byte hdwr sectors (250059 MB) Aug 27 18:48:32 linux-srv kernel: sdc: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sdc: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sdc: drive cache: write back Aug 27 18:48:32 linux-srv kernel: SCSI device sdc: 488397168 512-byte hdwr sectors (250059 MB) Aug 27 18:48:32 linux-srv kernel: sdc: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sdc: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sdc: drive cache: write back Aug 27 18:48:32 linux-srv kernel: sdc: sdc1 Aug 27 18:48:32 linux-srv kernel: sd 0:0:2:0: Attached scsi disk sdc Aug 27 18:48:32 linux-srv kernel: sd 0:0:2:0: Attached scsi generic sg2 type 0 Aug 27 18:48:32 linux-srv kernel: Vendor: ATA Model: WDC WD2500JB-00G Rev: 08.0 Aug 27 18:48:32 linux-srv kernel: Type: Direct-Access ANSI SCSI revision: 05 Aug 27 18:48:32 linux-srv kernel: SCSI device sdd: 488397168 512-byte hdwr sectors (250059 MB) Aug 27 18:48:32 linux-srv kernel: sdd: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sdd: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sdd: drive cache: write back Aug 27 18:48:32 linux-srv kernel: SCSI device sdd: 488397168 512-byte hdwr sectors (250059 MB) Aug 27 18:48:32 linux-srv kernel: sdd: Write Protect is off Aug 27 18:48:32 linux-srv kernel: sdd: Mode Sense: 00 3a 00 00 Aug 27 18:48:32 linux-srv kernel: SCSI device sdd: drive cache: write back Aug 27 18:48:32 linux-srv kernel: sdd: sdd1 Aug 27 18:48:32 linux-srv kernel: sd 0:0:3:0: Attached scsi disk sdd Aug 27 18:48:32 linux-srv kernel: sd 0:0:3:0: Attached scsi generic sg3 type 0 Aug 27 18:48:33 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16227]: new block device /block/sda Aug 27 18:48:35 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16437]: new block device /block/sdb Aug 27 18:48:35 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16467]: new block device /block/sdd Aug 27 18:48:35 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16487]: new block device /block/sdc Aug 27 18:48:35 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16587]: new block device /block/sdc/sdc1 Aug 27 18:48:35 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16599]: new block device /block/sdd/sdd1 Aug 27 18:48:37 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16611]: new block device /block/sdb/sdb1 Aug 27 18:48:38 linux-srv /etc/hotplug.d/block/50-hwscan.hotplug[16603]: new block device /block/sda/sda1 Aug 27 18:49:01 linux-srv hald[9182]: Timed out waiting for hotplug event 1950. Rebasing to 1930 What works: 1) Read performance to all 4 drives is ok (40-50 MBytes/sec as reported by iostat) and stable. I've hammered a read-only software RAID5 spread across the last 3 drives with no problem. 2) "smartctl -d ata -a" works nicely to all 4 drives. 3) hdparm -S makes the drives spin down when idle as expected. 4) Hotplug seems to work quite well. I'm even able to power down and remove a drive from the port multiplier while the other 3 are reading data (during a "e2fsck -f -n /dev/md0"). What doesn't work so well: 1) Writing to sda1. # dd if=/dev/zero of=/dev/sda1 count=4M <ctrl-c, then wait 30 seconds> 264205+0 records in 264204+0 records out 135272448 bytes (135 MB) copied, 111.373 seconds, 1.2 MB/s >From iostat -k 10: Device: tps kB_read/s kB_wrtn/s kB_read kB_wrtn sda 2428.64 2422.46 667.66 24273 6690 sda 36.84 23.72 1667.87 237 16662 sda 2440.60 2434.90 616.00 24349 6160 The read rate is curious (should be 0)... Top shows 1% user, 3% system, 93% wait. If I "cat /proc/scsi/sg/devices" during this test, the next to last column seems to indicate that the queue fills up and pretty much stays that way: # cat /proc/scsi/sg/devices 0 0 0 0 0 1 31 0 1 0 0 1 0 0 1 1 0 1 0 0 2 0 0 1 1 0 1 0 0 3 0 0 1 1 0 1 # cat /proc/scsi/sg/devices 0 0 0 0 0 1 31 29 1 0 0 1 0 0 1 1 0 1 0 0 2 0 0 1 1 1 1 0 0 3 0 0 1 1 1 1 # cat /proc/scsi/sg/devices 0 0 0 0 0 1 31 31 1 0 0 1 0 0 1 1 0 1 0 0 2 0 0 1 1 0 1 0 0 3 0 0 1 1 0 1 # cat /proc/scsi/sg/devices 0 0 0 0 0 1 31 30 1 0 0 1 0 0 1 1 0 1 0 0 2 0 0 1 1 1 1 0 0 3 0 0 1 1 0 1 2) hdparm -C for all 4 drives always shows "drive state is: standby" even when I'm certain that the drives are active. I'd really like some assistance debugging the write performance issue. The "hdparm -C" issue would be gravy... Thanks, Derek - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
