我有一台 HP MicroServer NL54，库存 BIOS，配有 4 个 HD Seagate Barracuda ST2000DM001 2TB 7200 RPM 64MB 缓存。
如果我运行 dd 基准测试，我会得到：
$ dd if=/dev/zero of=/dev/sdb bs=4K count=4096 4096+0 条记录输入 4096+0 条记录输出 16777216 字节（17 MB）已复制，3.52959 秒，4.8 MB/s
最大 4.8、4.9、5MB/s！
这是我的 dmesg：
[ 3.019637] ata1: PATA max UDMA/100 cmd 0x1f0 ctl 0x3f6 bmdma 0xff00 irq 14
[ 3.019681] ata2: PATA max UDMA/100 cmd 0x170 ctl 0x376 bmdma 0xff08 irq 15
[ 3.022465] ata3: SATA max UDMA/133 abar m1024@0xfe5ffc00 port 0xfe5ffd00 irq 43
[ 3.022509] ata4: SATA max UDMA/133 abar m1024@0xfe5ffc00 port 0xfe5ffd80 irq 43
[ 3.022552] ata5: SATA max UDMA/133 abar m1024@0xfe5ffc00 port 0xfe5ffe00 irq 43
[ 3.022594] ata6: SATA max UDMA/133 abar m1024@0xfe5ffc00 port 0xfe5ffe80 irq 43
[ 3.516847] ata5: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[ 3.516926] ata3: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[ 3.516998] ata4: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[ 3.517056] ata6: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
[ 3.517579] ata5.00: ATA-8: ST2000DM001-1E6164, SC48, max UDMA/133
[ 3.517628] ata5.00: 3907029168 sectors, multi 0: LBA48
[ 3.517695] ata4.00: ATA-8: ST2000DM001-1E6164, SC48, max UDMA/133
[ 3.517735] ata4.00: 3907029168 sectors, multi 0: LBA48
[ 3.518233] ata6.00: ATA-8: ST2000DM001-1CH164, CC24, max UDMA/133
[ 3.518284] ata6.00: 3907029168 sectors, multi 0: LBA48 NCQ (depth 31/32), AA
[ 3.518365] ata5.00: configured for UDMA/133
[ 3.518474] ata4.00: configured for UDMA/133
[ 3.519089] ata6.00: configured for UDMA/133
[ 3.523456] ata3.00: ATA-7: SAMSUNG HD502HI, 1AG01118, max UDMA7
[ 3.523502] ata3.00: 976773168 sectors, multi 0: LBA48 NCQ (depth 31/32), AA
[ 3.530067] ata3.00: configured for UDMA/133
[ 3.549678] sd 3:0:0:0: [sdb] 3907029168 512-byte logical blocks: (2.00 TB/1.81 TiB)
[ 3.549753] sd 3:0:0:0: [sdb] 4096-byte physical blocks
[ 3.549813] sd 4:0:0:0: [sdc] 3907029168 512-byte logical blocks: (2.00 TB/1.81 TiB)
[ 3.549856] sd 4:0:0:0: [sdc] 4096-byte physical blocks
[ 3.549860] sd 5:0:0:0: [sdd] 3907029168 512-byte logical blocks: (2.00 TB/1.81 TiB)
[ 3.549863] sd 5:0:0:0: [sdd] 4096-byte physical blocks
[ 3.549943] sd 5:0:0:0: [sdd] Write Protect is off
[ 3.549946] sd 5:0:0:0: [sdd] Mode Sense: 00 3a 00 00
[ 3.549965] sd 5:0:0:0: [sdd] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 3.550092] sd 2:0:0:0: [sda] 976773168 512-byte logical blocks: (500 GB/465 GiB)
[ 3.550194] sd 2:0:0:0: [sda] Write Protect is off
[ 3.550235] sd 2:0:0:0: [sda] Mode Sense: 00 3a 00 00
[ 3.550278] sd 2:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 3.550297] sd 3:0:0:0: [sdb] Write Protect is off
[ 3.550300] sd 3:0:0:0: [sdb] Mode Sense: 00 3a 00 00
[ 3.550319] sd 3:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 3.550531] sd 4:0:0:0: [sdc] Write Protect is off
[ 3.550576] sd 4:0:0:0: [sdc] Mode Sense: 00 3a 00 00
[ 3.550606] sd 4:0:0:0: [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 3.557986] sd 2:0:0:0: Attached scsi generic sg0 type 0
[ 3.558127] sd 3:0:0:0: Attached scsi generic sg1 type 0
[ 3.558335] sd 4:0:0:0: Attached scsi generic sg2 type 0
[ 3.558468] sd 5:0:0:0: Attached scsi generic sg3 type 0
[ 3.566284] sd 2:0:0:0: [sda] Attached SCSI disk
[ 3.572387] sd 3:0:0:0: [sdb] Attached SCSI disk
[ 3.583672] sd 4:0:0:0: [sdc] Attached SCSI disk
[ 3.610449] sd 5:0:0:0: [sdd] Attached SCSI disk
在 BIOS 中，它被配置为 AHCI。
有什么想法吗？
答案1
写入缓存：已禁用。是否要禁用写入缓存？如果不想，请执行hdparm -W1 /dev/sdb并验证是否已使用 进行更改hdparm -W /dev/sdb。重新运行测试。如果看起来更好，请添加write_cache = on到/etc/hdparm.conf。