Whole-Drive Fill

This test starts with a freshly-erased drive and fills it with 128kB sequential writes at queue depth 32, recording the write speed for each 1GB segment. This test is not representative of any ordinary client/consumer usage pattern, but it does allow us to observe transitions in the drive's behavior as it fills up. This can allow us to estimate the size of any SLC write cache, and get a sense for how much performance remains on the rare occasions where real-world usage keeps writing data after filling the cache.

The SLC write cache in the 1TB SK hynix Gold P31 runs out after just over 100GB of writes. After the SLC cache fills up, the Gold P31's sequential write performance becomes highly variable, ranging from about 1.4 to 2.3 GB/s with little change in character across the entire TLC filling phase. There are no obvious patterns of periodic garbage collection cycles visible at this scale.

Sustained 128kB Sequential Write (Power Efficiency)
Average Throughput for last 16 GB Overall Average Throughput

Despite the variability, the P31's long-term sustained write performance is excellent. It averages out to the best overall write throughput we've measured from a 1TB TLC drive, and in all that variation the performance never drops down to a disappointing level.

Working Set Size

Most mainstream SSDs have enough DRAM to store the entire mapping table that translates logical block addresses into physical flash memory addresses. DRAMless drives only have small buffers to cache a portion of this mapping information. Some NVMe SSDs support the Host Memory Buffer feature and can borrow a piece of the host system's DRAM for this cache rather needing lots of on-controller memory.

When accessing a logical block whose mapping is not cached, the drive needs to read the mapping from the full table stored on the flash memory before it can read the user data stored at that logical block. This adds extra latency to read operations and in the worst case may double random read latency.

We can see the effects of the size of any mapping buffer by performing random reads from different sized portions of the drive. When performing random reads from a small slice of the drive, we expect the mappings to all fit in the cache, and when performing random reads from the entire drive, we expect mostly cache misses.

When performing this test on mainstream drives with a full-sized DRAM cache, we expect performance to be generally constant regardless of the working set size, or for performance to drop only slightly as the working set size increases.

As expected for a drive with a full size DRAM buffer, the P31's random read latency is unaffected by spatial locality: reading across the whole drive is just as fast as reading from a narrow range. And the only other TLC drives that can match this read latency are the two Toshiba/Kioxia SSDs with 96L BiCS4 TLC NAND, but they can't maintain this performance across the entire test.

SK hynix Gold P31 1TB Review AnandTech Storage Bench
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  • surt - Thursday, August 27, 2020 - link

    Am i the odd one out that hasn't needed to use a hard drive tool in years?
  • HardwareDufus - Thursday, August 27, 2020 - link

    i don't think so. i've been in the industry for over 30 years. back in those days, some harddrives came with error lists that you had to key into a system bios. then there were all the size limits that require creating multiple partitions... the list goes on...

    but I think other than running scan disk once a year and my scheduled trims.... I haven't used a harddrive tool on my personal PCs and laptops for over 8 years.
  • plopke - Thursday, August 27, 2020 - link

    For me only once with Samsung it was needed , the other times where it was offered but not needed was crucial /sandisk for slight improved performance or compatibility. I just found it very awkward to not have a website showing specifications or support tools at all.
  • Holliday75 - Thursday, August 27, 2020 - link

    Nope. I have no updated the firmware on a SSD in 5+ years. That includes work.
  • MikeMurphy - Friday, August 28, 2020 - link

    My practice is to update firmware before I install a fresh copy of Windows. Often I'm greeted with some improved firmware for which I'm grateful. I've been happy with the support on my Crucial, Intel and Samsung drives.
  • TheinsanegamerN - Monday, August 31, 2020 - link

    Literally have never updated firmware on any SSD. Also only had issues with 1 SSD where the controller straight up died.
  • Tomatotech - Thursday, August 27, 2020 - link

    I've only ever used them as a last resort when trying to rescue a failing SSD (and I've had a couple) - they were useless anyway, might as well not bother. Both times when the drive died the manufacturer happily replaced the drive.

    With today's cloud tech it's easier than ever to keep a 1TB drive constantly backed up & synced (different things) to several different places. OneDrive offers 1TB, iCloud offers 2TB, etc, and usually anything apart from office docs, project files, and photos doesn't even need to be backed up.
  • TheinsanegamerN - Monday, August 31, 2020 - link

    That only applies to the 1% who can get fiber internet. Ever try to back up 1TB of stuff over a cable connection, usually with a 3-5Mbps upload speed?

    For most people an external HDD is more usable as a backup method then any cloud storage.
  • Srikzquest - Thursday, August 27, 2020 - link

    Hi Billy, I see that the benchmarks are equally compelling on the performance side as well in addition to power efficiency. Then, why its only the standard for Laptops and not Desktops. Is it due to PCIe gen4 drives on the market?
  • Billy Tallis - Thursday, August 27, 2020 - link

    The P31 is definitely a good choice for desktops, but it's not the only reasonable choice—while for laptops, it pretty much is at the moment. Since desktop users have little reason to worry about SSD power efficiency, it can make sense to go with something like a cheaper, somewhat slower Phison E12 drive or even something more low-end, because the real-world performance difference between the P31 and a decent low-end NVMe drive (or even a good SATA drive) is pretty small for most use cases. There's also the 2TB market to consider, since the Platinum P31 isn't available yet.

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