Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Follow up: I was hoping Lars or Phillip would provide some pointers, but I see that other various people have reported similiar problems an go unanswered.... I have been running this command to benchmark WRITE performance to the SCSI block device. The funny thing is that each additional run, the WRITE performace decreases... INTERESTING.... ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 71.87 MB/sec (3221225472 B / 00:42.745236) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 67.68 MB/sec (3221225472 B / 00:45.387656) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 60.62 MB/sec (3221225472 B / 00:50.679095) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 51.54 MB/sec (3221225472 B / 00:59.604501) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 46.71 MB/sec (3221225472 B / 01:05.771989) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 42.49 MB/sec (3221225472 B / 01:12.297245) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 39.35 MB/sec (3221225472 B / 01:18.063164) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 38.00 MB/sec (3221225472 B / 01:20.845423) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 35.44 MB/sec (3221225472 B / 01:26.670520) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 34.32 MB/sec (3221225472 B / 01:29.512314) ./dm -a 0 -b 1M -s 3G -y -m -p -o /dev/sdb 33.47 MB/sec (3221225472 B / 01:31.781341) (linux-kernel 2.6.20.3) Adaptec aacraid driver (1.1-5[2423]-mh3) ACPI: PCI Interrupt 0000:04:08.1[A] -> GSI 30 (level, low) -> IRQ 17 AAC0: kernel 2.8-1[6098] AAC0: monitor 2.8-1[6098] AAC0: bios 2.8-1[6098] AAC0: serial 80d081d3 scsi0 : percraid scsi 0:0:0:0: Direct-Access DELL PERC Mirror V1.0 PQ: 0 ANSI: 2 scsi 0:0:1:0: Direct-Access DELL PERC Volume V1.0 PQ: 0 ANSI: 2 megasas: 00.00.03.05 Mon Oct 02 11:21:32 PDT 2006 SCSI device sda: 71091456 512-byte hdwr sectors (36399 MB) sda: assuming Write Enabled sda: assuming drive cache: write through SCSI device sda: 71091456 512-byte hdwr sectors (36399 MB) sda: assuming Write Enabled sda: assuming drive cache: write through sda: sda1 sda2 sda3 < sda5 > sd 0:0:0:0: Attached scsi removable disk sda SCSI device sdb: 71677440 512-byte hdwr sectors (36699 MB) sdb: assuming Write Enabled sdb: assuming drive cache: write through SCSI device sdb: 71677440 512-byte hdwr sectors (36699 MB) sdb: assuming Write Enabled sdb: assuming drive cache: write through sdb: unknown partition table sd 0:0:1:0: Attached scsi removable disk sdb sd 0:0:0:0: Attached scsi generic sg0 type 0 sd 0:0:1:0: Attached scsi generic sg1 type 0