In March of 2012, I purchased a WD 3TB MyBook, which comes with a MicroUSB 3.0 SuperSpeed connector, and a SYBA USB 3.0 PCI Express add-in card for my Ubuntu Linux server. I was running Ubuntu Linux 11.10 which was current at that time. When I first started using the new MyBook with USB 3.0, if I tried moving large amounts of data, like a full system backup, I would quickly get errors in dmesg related to the USB 3.0 ports and the MyBook would disappear. Not only that, but the USB 3.0 adapter card became entirely unusable until the next reboot. If I copied only smaller chunks like audio/video files under a gigabyte, I would not see any issues, but attempting to copy 5GB or more would often trigger the errors and require a reboot to restore access to the USB 3.0 ports. Using that same MyBook with USB 2.0 never had issues, but was just a lot slower.
At the time, I considered that maybe Linux's support for USB 3.0 was weak, at least in the kernels that come with that version of Ubuntu, or maybe either my MyBook or SYBA adapter just had buggy USB 3.0 support. Since then, I've purchased a NexStar SATA to USB 3.0 adapter in September 2012, and later, an UltraTech USB 3.0 PCI Express in August 2013. I've had issues with all combinations of hardware so it appears to not be an issue with either the USB device or adapter board. That leads me to believe that it's an issue with the Linux Kernel drivers for USB 3.0. I've updated my server through each release of Ubuntu Linux and am now on 14.04 LTS and still see errors occurring. Things have improved, though, as I don't need to reboot to fix issues, just unplug and plug in the hard drives back in if they disappear. They also seem to disappear far less often, but I still see regular errors in dmesg and still have to occasionally re-connect the drives to get them to come back. Both USB drives work fine on USB 2.0 connections on the same computer. Here's the two USB adapter cards I've purchased: http://amzn.com/B00CBDZ1NU http://www.newegg.com/Product/Product.aspx?Item=N82E16815124101&RandomID=92627712361355620140519172217 In a speed test I just ran, I only saw about 387 Mbps which is more of a USB 2.0 speed than a 3.0 speed. Here's an example of one error I often see in dmesg: [ 166.940310] WARNING: CPU: 0 PID: 5389 at /build/buildd/linux-3.13.0/drivers/usb/host/xhci-ring.c:1589 handle_cmd_completion+0xde4/0xe40() [ 166.940312] Modules linked in: nls_iso8859_1 pci_stub vboxpci(OF) vboxnetadp(OF) vboxnetflt(OF) vboxdrv(OF) ib_srpt tcm_qla2xxx qla2xxx tcm_loop tcm_fc libfc scsi_transport_fc [ 166.940384] CPU: 0 PID: 5389 Comm: update-manager Tainted: PF O 3.13.0-24-generic #46-Ubuntu [ 166.940386] Hardware name: MICRO-STAR INTERNATIONAL CO.,LTD MS-7380/MS-7380, BIOS V2.1 07/11/2008 [ 166.940387] 0000000000000009 ffff88011fc03da8 ffffffff81715a64 0000000000000000 [ 166.940391] ffff88011fc03de0 ffffffff810676bd ffff8801146b65d0 0000000000000000 [ 166.940394] ffff8801146b63c0 00000001146b63c0 ffff8801196f4000 ffff88011fc03df0 [ 166.940397] Call Trace: [ 166.940398] <IRQ> [<ffffffff81715a64>] dump_stack+0x45/0x56 [ 166.940405] [<ffffffff810676bd>] warn_slowpath_common+0x7d/0xa0 [ 166.940408] [<ffffffff8106779a>] warn_slowpath_null+0x1a/0x20 [ 166.940410] [<ffffffff81574224>] handle_cmd_completion+0xde4/0xe40 [ 166.940414] [<ffffffff810992b4>] ? scheduler_tick+0xa4/0xf0 [ 166.940416] [<ffffffff81575cc3>] xhci_irq+0x333/0xa60 [ 166.940419] [<ffffffff8101b763>] ? native_sched_clock+0x13/0x80 [ 166.940421] [<ffffffff81576401>] xhci_msi_irq+0x11/0x20 [ 166.940424] [<ffffffff810bf6ae>] handle_irq_event_percpu+0x3e/0x1d0 [ 166.940427] [<ffffffff810bf87d>] handle_irq_event+0x3d/0x60 [ 166.940429] [<ffffffff810c2257>] handle_edge_irq+0x77/0x130 [ 166.940432] [<ffffffff81015cde>] handle_irq+0x1e/0x30 [ 166.940435] [<ffffffff8172874d>] do_IRQ+0x4d/0xc0 [ 166.940438] [<ffffffff8171deed>] common_interrupt+0x6d/0x6d [ 166.940440] <EOI> _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
