Low negotiated link speed

Why haven't you replaced the hard drive cable as you was suggested by several people including myself in your original thread here about hard drive issues with this laptop? Until you do this you are wasting everyone's time here.

The hard drive cable in the MacBook Pro 13" has an EXTREMELY HIGH rate of failure. It was so bad Apple actually would proactively replace the cable for free whenever the laptop was serviced even if the drive appeared to be working fine. If you connect the drive externally and everything works, this is almost certain confirmation the internal cable is bad. Every drive will handle the defective cable differently.

FYI, some older SATA hard drives actually had a jumper for forcing the drive to SATA I 1.5Gb/s mode for compatibility reasons.

Hello,

Link Speed is the maximum speed the SATA port can handle, Negotiated Speed is (just what it says) the current "Negotiated" speed; when the negotiated speed is lower than the link speed it means something isn't capable of *reliable* transfer at the link speed, could be the drive or the cable, or even a high error rate; check the drive spec first (see if it's capable), then have a good look at the cables (or back-plane) & SATA connectors.

As example...

Special note for specific 2009 iMacs, 2008-2010 MacBooks, 2008-2009 MacBook Pros & 2009 Mac mini.

We highly recommend the use of a SATA 2.0 (3Gb/s) SSD such as the OWC Mercury Electra 3G for the following Macs:

iMacs w/ Model ID:

• iMac9,1
• iMac10,1
• iMac11,1

MacBooks w/ Model ID:

• MacBook5,1
• MacBook5,2
• MacBook6,1
• MacBook7,1

MacBook Pros w/ Model ID:

• MacBookPro5,1
• MacBookPro5,2
• MacBookPro5,3
• MacBookPro5,4
• MacBookPro5,5

Mac minis w/ Model ID:

• Macmini3,1
• Macmini4,1

While a 6G SSD does function, it will only do so at SATA Revision 1.0 (1.5Gb/s, 150MB/s) speeds rather that the SATA Revision 2.0 (3.0Gb/s 300MB/s) speed the computer can deliver.

The Mercury Electra 3G SSD is the OWC recommended upgrade option for the Macs listed in the special note above.

https://eshop.macsales.com/item/OWC/S3D7E6G500/

Plus, I doubt a 5400 RPM drive could saturate 1.5Gb/s

If you want a faster negotiated speed, replace the drive.

The drive you are using (a spinning hard drive, as denoted by the 'Medium Type: Rotational' line) can only support a 1.5Gbps link. That's not uncommon for a spinning disk. Faster link speeds (and throughput) can be achieved with larger drives and solid state (e.g. SSD) drives.

Hi,

Toshiba MQ01ABD050 - hard drive - 500 GB - SATA 3Gb/s Specs...

https://www.cnet.com/products/toshiba-mq01abd050-hard-drive-500-gb-sata-3gb-s-mq01abd050/

Another 5400 RPM drive supposedly capable of 3Gb/s but wasted on a 5400 RPM drive...

https://hdd.userbenchmark.com/Compare/Toshiba-MQ01ABF050-500GB-vs-Group-/m2789vs10

1.5 Gbps = 187.5 MB/s, drive only can do https://hdd.userbenchmark.com/SpeedTest/147091/WDC-WD4002FYYZ-01B7CB0

HGST still 5200 RPM, 1.5 Gbps = 187.5 MB/s, drive only can do 77.9 MB/s

https://hdd.userbenchmark.com/Compare/HGST-Travelstar-7K750-25--500GB-vs-Group-/m789vs10

7200 RPM WD4002FYYZ better

https://hdd.userbenchmark.com/SpeedTest/147091/WDC-WD4002FYYZ-01B7CB0

My 500 GB in iMac...

Intel 6 Series Chipset:

Vendor: Intel

Product: 6 Series Chipset

Link Speed: 6 Gigabit

Negotiated Link Speed: 3 Gigabit

Physical Interconnect: SATA

Description: AHCI Version 1.30 Supported

ST3500418AS:

Capacity: 500.11 GB (500,107,862,016 bytes)

Model: ST3500418AS

Revision: AP73

Serial Number: Z2AVD0D8

Native Command Queuing: Yes

Queue Depth: 32

Removable Media: No

Detachable Drive: No

BSD Name: disk0

Rotational Rate: 7200

Medium Type: Rotational

Partition Map Type: GPT (GUID Partition Table)

S.M.A.R.T. status: Verified

If you want speed...

https://eshop.macsales.com/shop/ssd/owc/imac-27-inch/2011

https://www.storagereview.com/owc_mercury_extreme_pro_6g_ssd_review_240gb

I'm still in HDD & will be for awhile.

It's up to the Drive to negotiate the speed, for instance most 6Gb/s drives can negotiate 3 speeds to accommodate older machines... 6Gb/s, 3Gb/s, & 1.5Gb/s, here's the script...

Os: Hello, hello, hello...

Drive: I speak 1.5Gb/s... 3Gb/s... 6Gb/s

Os: OK I understand you speak 1.5Gb/s, what size are you...

Drive: 500 GB...

Os: Hello, hello, hello...

Drive: I speak 6Gb/s, 3Gb/s, 1.5Gb/s

Os: OK I understand you speak 6Gb/s, what size are you...

Drive: 500 GB...

Doesn't really matter if your drive negotiated a speed of 6Gb/s, it cannot even approach 1.5Gb/s, if you had a good 7200 or 10,000 RPM drive with a 64 MB cache or bigger it would negotiate a faster speed, but it depends in how the drive responds & how fast it responds... no use of the OS devoting cycles to a 3Gb/s negotiation, which has to be checked twice as often as a 1.5Gb/s negotiated if the OS is going to be waiting for data from the drive even at the slowest negotiation. :)

Your Drives say 3Gb/s because they'll also work in systems that only do 3Gb/s, not that the drive can do that.

Hard disks don’t need faster I/O buses, and not the least of which are these low-RPM hard disks...

Replace the hard disk with an SSD.

Downhill with a tailwind, rotating rust—a hard disk drive—might hit 200 I/Os per second, and that’s only with a much faster disk than what’s shown here, and with favorable I/O patterns..

An SSD will be far, far, far, far faster. A glacial, old, slow SSD will provide 5,000 I/Os per second, and a typical SSD model now found on various Macs will provide ~100,000 I/Os per second. Some are faster. These faster I/O buses are intended for SSDs and for NVMe storage. Not for hard disks. Which might manage ~200 I/O operations per second, with a 15,000 RPM hard disk on a SAS I/O bus. You don’t have a 15K RPM disk here, either.

Some details on latency follow, which is how fast data can be accessed—bandwidth is how much can be gotten and how fast. What’s another way of looking at latency and bandwidth? A delivery truck filled with disk drives has massive bandwidth, and rotten latency. Hard disks have rotten latency, as compared to NVMe and SSD and main memory.

https://people.eecs.berkeley.edu/~rcs/research/interactive_latency.html

As for device operations and reliability? Have a look at how wacky a hard disk really is. Moving parts and motors, very tight tolerances, flying heads and fluid dynamics, sensitivity to shocks and even to loud sounds, etc. On the plus side, head crashes are a whole lot less impressive in recent years.

https://m.youtube.com/watch?v=enQ-zrNSSM4

https://m.youtube.com/watch?v=tDacjrSCeq4

Whew, great to hear! :)

Good work.