[Solved] Slow preclear speed on HP Proliant N40L

[EDIT] Problem fixed by turning on write caching in the BIOS. Hope this info will be useful to anyone else with this server.  Now getting preclear speed of 125MB/s instead of 13MB/s

I'd still like to know why when issuing the preclear command which is supposed to list disks not assigned to unraid (./preclear_disk.sh -l) it lists all 3 drives in the server, even though 2 of them are assigned to the array as 1x parity and 1x data which it shouldn't do. Anyone know? This has never happened with my main 17 drive server.

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[Original problem] Hello everyone. I've just setup a HP Proliant microserver as my second unRAID box.

I'm currently trying to preclear a third disk to add as my second data disk but unfortunately it's only pre-reading the data at around 13MB/s and has taken about 10 hours to get to 49% pre-read.

I've checked the BIOS and it's set to ACHI mode. I noticed in the POST as it boots it does say for all 3 drives: Auto-Detecting AHCI Port .. IDE Hard Disk but I didn't notice any trouble or very slow speeds when pre-clearing the other 2 drives. I also used the HP microserver to preclear a 3TB drive for my main unRAID server and it precleared that drive in the normal time it takes to clear a 3TB drive (around 27 hours).

Another issue to note is when I issued the preclear command which is supposed to list disks not assigned to unraid (./preclear_disk.sh -l) it listed all 3 drives in the server, even though 2 of them are assigned to the array as 1x parity and 1x data which it shouldn't do.

I assume the problem is with the particular 1TB disk I'm trying to preclear as in the syslog there are lots of red errors reported every once in a while:

Dec 30 14:45:04 MicroServer kernel: Pid: 0, comm: kworker/0:0 Not tainted 3.0.35-unRAID #2 (Errors)

Dec 30 14:45:04 MicroServer kernel: Call Trace: (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c105fee8>] warn_alloc_failed+0xb2/0xc4 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1060653>] __alloc_pages_nodemask+0x456/0x47f (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12922bb>] ? skb_copy+0x2e/0x83 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c10606d0>] __get_free_pages+0xf/0x21 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c107ea03>] __kmalloc_track_caller+0x2c/0xed (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c129182f>] __alloc_skb+0x53/0xf1 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12922bb>] skb_copy+0x2e/0x83 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<f845b3a2>] tigon3_dma_hwbug_workaround+0x36/0x1b1 [tg3] (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<f845bbe3>] tg3_start_xmit+0x6c6/0x7ab [tg3] (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1298362>] dev_hard_start_xmit+0x24b/0x322 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12a6d6a>] sch_direct_xmit+0x50/0x137 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1298537>] dev_queue_xmit+0xfe/0x274 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12b3d4f>] ip_finish_output+0x237/0x272 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12b3e2a>] ip_output+0xa0/0xa8 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12b326e>] ip_local_out+0x1b/0x1e (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12b3772>] ip_queue_xmit+0x2a5/0x2f2 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c2ce8>] tcp_transmit_skb+0x4d7/0x50d (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c0a09>] ? tcp_clean_rtx_queue+0x5f2/0x6da (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c4ff2>] tcp_write_xmit+0x2f9/0x3d7 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c5114>] __tcp_push_pending_frames+0x18/0x6f (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c19c3>] tcp_rcv_established+0xfa/0x577 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c71c6>] tcp_v4_do_rcv+0x46/0x137 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12c769a>] tcp_v4_rcv+0x3e3/0x664 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12afb90>] ip_local_deliver_finish+0xba/0x192 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12afcc9>] ip_local_deliver+0x61/0x66 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12af851>] ip_rcv_finish+0x23d/0x253 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c12afaa0>] ip_rcv+0x239/0x26f (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1295d8d>] __netif_receive_skb+0x23a/0x260 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1297256>] netif_receive_skb+0x5d/0x63 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c129731d>] napi_skb_finish+0x1e/0x34 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1297794>] napi_gro_receive+0xed/0xf5 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<f845d4da>] tg3_rx+0x3f9/0x54b [tg3] (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<f845d68b>] tg3_poll_work+0x5f/0x11a [tg3] (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<f845d8a2>] tg3_poll+0xae/0x1e8 [tg3] (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c129786a>] net_rx_action+0x59/0x12a (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c102d13a>] __do_softirq+0x6b/0xe5 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c102d0cf>] ? irq_enter+0x3c/0x3c (Errors)

Dec 30 14:45:04 MicroServer kernel:  <IRQ>  [<c102cf8d>] ? irq_exit+0x32/0x53

Dec 30 14:45:04 MicroServer kernel:  [<c1003667>] ? do_IRQ+0x7c/0x90 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c13102a9>] ? common_interrupt+0x29/0x30 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1007efc>] ? default_idle+0x2e/0x43 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1008027>] ? amd_e400_idle+0xb1/0xcb (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c1001a89>] ? cpu_idle+0x3a/0x51 (Errors)

Dec 30 14:45:04 MicroServer kernel:  [<c130b137>] ? start_secondary+0xad/0xaf (Errors)

Is there a way to fix this or is the drive no good and I should not bother with it in my array?

I cancelled the first attempt when I rebooted to check the BIOS AHCI settings. It's set to ACHI mode but I couldn't see any IDE Emulation or Legacy mode options to disable.

Full syslogs of both attempts included.

Thank you for any guidance,

Ben

MicroServer_syslogs.zip