Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1694668 > unrolled thread

USB disk speed regression WD Elements - with bisect result 22547c4cc4fe20698a6a85a55b8788859134b8e4

Back to article view | Back to linux.kernel

Contents

  USB disk speed regression WD Elements - with bisect result  22547c4cc4fe20698a6a85a55b8788859134b8e4 Zdenek Kabelac <zkabelac@redhat.com> - 2017-07-24 14:10 +0200
    Re: USB disk speed regression WD Elements - with bisect result  22547c4cc4fe20698a6a85a55b8788859134b8e4 Alan Stern <stern@rowland.harvard.edu> - 2017-07-24 16:50 +0200
      Re: USB disk speed regression WD Elements - with bisect result  22547c4cc4fe20698a6a85a55b8788859134b8e4 Guenter Roeck <linux@roeck-us.net> - 2017-07-24 23:10 +0200

#1694668 — USB disk speed regression WD Elements - with bisect result 22547c4cc4fe20698a6a85a55b8788859134b8e4

Hi

I've problem with my USB storage devices:  WD Elements 1TB.
(Bus 004 Device 002: ID 1058:10a8 Western Digital Technologies, Inc. Elements 
Portable (WDBUZG))


After kernel >4.9  when disk is attached via cable it has very low speed 
(less then 1MB/s).

It can run at full speed (>22MB/s) when the Linux kernel is fully rebooted (so 
disk is attached during the reboot of Lenovo T61, C2D, Fedora Rawhide).

However when >4.9 kernel is running and disk is just attached it's very slow.

I've played a bisect game - and the clean result has been:

22547c4cc4fe20698a6a85a55b8788859134b8e4

When I just revert this patch with 4.13-rc1 - it's again running with full 
speed even when disk is attached (thus no reboot is needed for full speed).


So while I've no idea what 22547c4cc4fe20698... is doing, it seems to have 
some unpleasant side-effect on regular USB devices.

So what else is needed to get this properly working ?
(assuming plain revert of  22547c4cc4fe20698 is unwanted).

What more info can I provide to get this storage 'normally' usable without 
rebooting the machine.

Regards

Zdenek

[toc] | [next] | [standalone]

#1694770

On Mon, 24 Jul 2017, Zdenek Kabelac wrote:

> Hi
> 
> I've problem with my USB storage devices:  WD Elements 1TB.
> (Bus 004 Device 002: ID 1058:10a8 Western Digital Technologies, Inc. Elements 
> Portable (WDBUZG))
> 
> 
> After kernel >4.9  when disk is attached via cable it has very low speed 
> (less then 1MB/s).
> 
> It can run at full speed (>22MB/s) when the Linux kernel is fully rebooted (so 
> disk is attached during the reboot of Lenovo T61, C2D, Fedora Rawhide).
> 
> However when >4.9 kernel is running and disk is just attached it's very slow.
> 
> I've played a bisect game - and the clean result has been:
> 
> 22547c4cc4fe20698a6a85a55b8788859134b8e4
> 
> When I just revert this patch with 4.13-rc1 - it's again running with full 
> speed even when disk is attached (thus no reboot is needed for full speed).
> 
> 
> So while I've no idea what 22547c4cc4fe20698... is doing, it seems to have 
> some unpleasant side-effect on regular USB devices.
> 
> So what else is needed to get this properly working ?
> (assuming plain revert of  22547c4cc4fe20698 is unwanted).
> 
> What more info can I provide to get this storage 'normally' usable without 
> rebooting the machine.

Please post the dmesg logs showing what happens when the disk is 
first attached and operates slowly, and what happens when the disk is 
attached following a reboot and operates normally.

Alan Stern

[toc] | [prev] | [next] | [standalone]

#1695097

On Mon, Jul 24, 2017 at 10:41:12AM -0400, Alan Stern wrote:
> On Mon, 24 Jul 2017, Zdenek Kabelac wrote:
> 
> > Hi
> > 
> > I've problem with my USB storage devices:  WD Elements 1TB.
> > (Bus 004 Device 002: ID 1058:10a8 Western Digital Technologies, Inc. Elements 
> > Portable (WDBUZG))
> > 
> > 
> > After kernel >4.9  when disk is attached via cable it has very low speed 
> > (less then 1MB/s).
> > 
> > It can run at full speed (>22MB/s) when the Linux kernel is fully rebooted (so 
> > disk is attached during the reboot of Lenovo T61, C2D, Fedora Rawhide).
> > 
> > However when >4.9 kernel is running and disk is just attached it's very slow.
> > 
> > I've played a bisect game - and the clean result has been:
> > 
> > 22547c4cc4fe20698a6a85a55b8788859134b8e4
> > 
> > When I just revert this patch with 4.13-rc1 - it's again running with full 
> > speed even when disk is attached (thus no reboot is needed for full speed).
> > 
> > 
> > So while I've no idea what 22547c4cc4fe20698... is doing, it seems to have 
> > some unpleasant side-effect on regular USB devices.
> > 
> > So what else is needed to get this properly working ?
> > (assuming plain revert of  22547c4cc4fe20698 is unwanted).
> > 
> > What more info can I provide to get this storage 'normally' usable without 
> > rebooting the machine.
> 
> Please post the dmesg logs showing what happens when the disk is 
> first attached and operates slowly, and what happens when the disk is 
> attached following a reboot and operates normally.
> 

Only idea I came up with is that some device may require more than one
port reset. Agreed, dmesg logs should give us an idea if this is the case.

I ordered one of those drives; maybe I can reproduce the problem.

Guenter

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web