I recently acquired a Lenovo Yoga 2 13. While, at the time, the Yoga 3 was available, I decided to go for Yoga 2 13. The Yoga 3 comes with the newer Core M Broadwell family, which, in my opinion, doesn't really bring any astounding benefits.
The Yoga 2 13 comes in mulitple variants worldwide. Infact these hardware variations have different effets when run under Linux.
My varaint of Yoga 2 13 is:
Storage
The drive runs into serious performance problems when its SSHD's NCQ (mis)feature is under use in Linux <= 4.0.
In the interim, to overcome this problem, we can force the device to run in degraded mode. I'm not sure if it is really the degraded mode, or the device was falsely advertised as a 6 GiB capable device. Time will tell, but for now, force it to run in 3 GiB mode, and so far, I haven't run into the above mentioned probems. To force 3 GiB speed, apply the following.
And then verify it... As you can see below, I've forced it for ata1 because I want my SSD drive to run at full-speed. I've done enough I/O, which earlier resulted in the kernel spitting the SATA errors. With this workaround, the kernel does not spit any error messages.
And the throughput you get out of your WD SATA SSHD drive, with capability set to 3.0 GiB is:
Hannes Reinecke has submitted patches for NCQ enhancements, for Linux 4.1,
which I hope will resolve these problems. Another option is to disable NCQ for the drive, or else blacklist the make/model in driver/ata/libata-core.c
By the time I finished this blog entry draft, I had tests to conclude that this did not look like an NCQ problem. Because in degraded mode too, it runs with NCQ enabled (check above).
Another interesting feature of this drive is support for TRIM / DISCARD. This drive's FTL accepts the TRIM command. Ofcourse, you need to ensure that you have discard enabled in all the layers. In my case, SATA + Device Mapper (Crypt and LVM) + File System (ext4)
Display
The overall display of this device is amazing. It is large enough to give you vibrant look. At 1920x1080 resolution, things look good. The display support was available out-of-the-box.
There were some suspend / resume hangs that occured with kernels < 4.x, during suspend / resume. The issue was root caused and fixed for Linux 4.0.
You may still notice the following kernel messages, though not problematic to me so far.
You may need to disable the Intel Management Engine Interface (mei.ko), incase you run into suspend/resume problems.
You may also run into the following Kernel Oops during suspend/resume. Below, you see 2 interation of sleep because it first hibernates and then sleeps (s2both).
There is one more occasional Kernel Oops (below), which I believe again has to do with Intel.
Network
In my case, the laptop came with the Realtek Wireless device (details above in lspci output). Note: The machine has no wired interface.
While the Intel Wifi devices shipped with this laptop have their own share of problems, this device (rtl8723be) works out of the box. But only for a while. There is no certain pattern on what triggers the bug, but once triggered, the network just freezes. Nothing is logged.
If your Yoga 2 13 came with the RTL chip, the following workaround may help avoid the network issues.
MCE
Almost every boot, eventually, the kernel reports MCE errors. Not something I understand well, but so far, it hasn't caused any visible issues. And from what I have googled so far, nobody seems to have fixed it anywhere
So, with fingers crossed, lets just hope this never translates into a real problem.
What the kernel reports of the CPU's capabilities.
The MCE logs extracted from the buffer.
Categories:
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Computing
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Keywords:
Lenovo
Yoga
Yoga 2 13
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