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Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by toomanybeersies on Monday January 04, 2016 @06:58AM (#10835065)
With SSDs and the density of network traffic these days, both indicator lights are pretty much obsolete. Your HDD activity light would never be on, and the network activity light would constantly be on.
Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by dingo_bat on Monday January 04, 2016 @12:58PM (#10837133)
Maybe you can set the network light to light up only when the utilization is above a certain level? Same goes for HDD light, we can use something like active time every 100 ms. My point is, these are useful things and it doesn't make much sense to remove them just to save some small fraction of a dollar.
Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by anc84 on Monday January 04, 2016 @07:08AM (#10835117)
You could simply normalise them to not be constantly on then.
Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by icebraining on Monday January 04, 2016 @07:11AM (#10835127)
As an user of a X201 with an SSD, that's not really the case, the differences of blinking rate are noticeable.
Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by dogma1138 on Monday January 04, 2016 @07:18AM (#10835158)
AHCI and NVMe don't support this type of activity polling so I don't have a clue what your X201 bases the HDD usage off but it's really not the old IDE standard LED blinking, which makes me thing it's either faked intentionally or the same thing that will happen if you plug in a modern SATA to a motherboard with HDD activity monitoring it will just blink erratically regardless of what is actually happening.

modern SATA drives doesn't matter if they are still mechanical or SSD's don't work the same, your OS doesn't work the same when you save a file it doesn't mean that it's being written that moment, it can be in RAM, it can be in your HDD's cache or it can be written down.

HDD activity LED's haven't been doing anything real for over a decade now...

Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by icebraining on Monday January 04, 2016 @09:50AM (#10835845)
I don't see why would you need AHCI or NVMe support, the activity "reporting" is done at a lower level.

From what I can tell, this feature is called "Device Activity Signal", and it essentially says the drive can use the P11 pin of the SATA connector to indicate activity, and the board can use this to electrically drive the LED, there's no need for high-level protocol support.

Obviously this won't detect writes to the buffer, only when they are actually pushed to the disk, but when there's heavy IO, the two are usually correlated.

Here's a doc by Samsung about DAS from 2014: http://www.samsung.com/global/business/semiconductor/minisit...

As a user, I can tell you that while I obviously can't relate a single "blink" with a write to a file, the link between having a bunch of processes hung waiting for IO and a heavily active LED is quite noticeable - and can be useful if the UI is completely blocked.

Re:Lenovo Launches ThinkPad X1 Yoga at CES with OLED Display by dogma1138 on Monday January 04, 2016 @09:56AM (#10835869)
DAS in SATA is pushed back over the power cable (pin 11) not the data connector like in ATA/IDE drives it's pretty much meaningless and up the the drive manufacturer to say if it's even supported, which is why for dekstop drives that are fed directly from the power supply the LED activity monitoring doesn't work at all and depending on your BIOS will either be off or just randomly signaling at best based on some data from your PCH.

Samsung for example only supports it on the DC (datacenter) series of their drives which is for enterprise storage the DAS in this case is only enabled in certain modes to note if the drive is active or spare/standby or to identify a specific drive there is no actual write/read iop activity feed back in SATA drives.

Also dear lord was that document auto-translated? I've expected this level of English from a 3rd tier Chinese OEM not Samsung...

>4. Samsung SSDs for data centers are

Basically, Samsung SSD 845DC PRO and 845DC EVO support the SATA 3.1 specifications. However, Samsung has adjusted only the DAS feature as “enabled” by default to make the LED blink regardless of the SATA specifications in the host systems.