This issue has been resolved for me by using kernel version 3.0+!
Greetings all! I've owned my PanP7 for a couple weeks now, and I'm absolutely in love with it. Honestly, I'm really glad that I went for the custom built laptop instead of trying (and failing) to get a Windows Tax refund from some other manufacturer.
I'm wondering if any other System76 users are experiencing this problem. I feel like I can't be the only System76 user to have experienced this problem, but I'm not blaming the company by any means.
On the PanP7, I'm running the 64-bit version of Lucid, and one thing that I've run into is that USB 2.0 performance can be quite laggy when transferring large files to an external drive (this has been documented many, many times across various linux distros since at least 2007, so I'll skip the reference links here - search linux USB 2.0 slow and you'll get thousands of hits). Transfers begin quickly, but then bottom out after a few hundred megabytes - eventually lagging somewhere in the area of 1 Mbps (regardless of file system type, and I've tested between FAT32, NTFS, and ext2 with the same results). For me, this happens between different USB thumb drives and an external hard drive, none of which experience this problem on my desktop nor under Windows. eSata works very quickly on the PanP7 for the external hard drive under Lucid.
Now before I asked for assistance here, I did do some research into this matter. Some forum posts suggested adding an "evelator=[X]" to the end of the kernel string in grub (see: http://ubuntuforums.org/showthread.p...33#post8124833). Some people reported success with this method, others not so much.
Others suggested (and I'm more convinced of this) that the underlying cause is the ehci_hcd module, and this can be fixed by unloading it and then reloading with
Code:
sudo modprobe -r ehci_hcd
sudo modprobe ehci_hcd
My questions to the System76 community would be then:
- Has anyone else experienced this problem?
- What do you do to correct it?
Trying the above command to unload the module, the command line returns: "FATAL: Module ehci_hcd is builtin" since in the newest Ubuntu kernels this module is not separate any longer!
From what I've read, I do think this is related to Intel chipsets. I already attempted to disable Legacy USB support in the BIOS and it rendered the same results.
So yeah. I'm pretty stumped. Any and all help would be appreciated! I can post any error logs or whatnot that would be helpful. Please just let me know how to get that info.
[Update] I may try to compile a new kernel with the Anticipatory I/O Scheduling instead of CFQ, like the above linked post spoke about. Does anyone have any input or advice on this for the PanP7? I'm currently backing up my system partition with Clonezilla and I might try this. The only thing that makes me pause is that the above post is an old post and I'm not sure if it would even do me any good.
Does anyone know of how I might test the "elevator=" method above? I do not have a /boot/grub/menu.lst.
[Update 2] I did more reading and found out about the changes to GRUB2. So I held down the shift key and got to the grub menu, manually added the evelator=as to enable Anticipatory I/O Scheduling and then booted to Lucid. ...And the change did nothing.
So I'm guessing that either this did not work, or this is not the cause of the problem.
I'm STILL STUCK! ARRRRRRG!!
Thank you in advance!
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