SSD endurance evaluation

[Alessandro 123]

Hi to all
Let's assume an hardware raid with 4 spinning disks where (more or less) each disk has wrote about 22061GB in 16083 hours (i've seen this from SMART output)

This means about 22061/16083*24 = 33GB writes per day.

If the SSD I would like to use (Intel S3610 480GB) is rated about 3DWPD (480*3=1440GB), this SSD would be absolutely OK in my environment, right ?

it should be able to survive for 5 years at writing, EVERY DAY, 40 times what I've wrote in about 2 year

Is this correct?

 

[Q-wulf]

Intel SSD DC S3610 480GB, 2.5", SATA (SSDSC2BX480G401
TBW: 3.7PB
source: http://www.intel.com/content/dam/ww.../product-specifications/ssd-dc-s3610-spec.pdf


you probably also wanna read up on
https://en.wikipedia.org/wiki/Write_amplification


My gut feeling says, that without taking write amplification into account, the SSD you stated at 3,7PB rating will do 2TB/day (5years*365days). That should probably be fine (it is one of the higher rated SSDs out in the wild regarding TBW)


ps.: you going single SSD or Raid setup again ?

 

[robhost]

If the SSD I would like to use (Intel S3610 480GB) is rated about 3DWPD (480*3=1440GB), this SSD would be absolutely OK in my environment, right ?

Yes, you could even use a SSD designed for mixed or read intense enviroments (i.e. Samsung PM863).

 

[Alessandro 123]

ps.: you going single SSD or Raid setup again ?

RAIDZ2

Write Amplification with ZFS should be limited due to the COW, right ?

 

[Q-wulf]

Yes, you could even use a SSD designed for mixed or read intense enviroments (i.e. Samsung PM863).

Samsung SSD PM863 480GB, SATA (MZ-7LM480E/MZ-7LM480Z)
rating: TBW: 700TB

For completeness sake (since i ran the numbers last night - prices are prosumer):

Samsung SSD PM863 480GB 310€ - 0.44€ / TBW
Intel SSD DC S3610 480GB 415€ - 0.11€ / TBW
Intel SSD DC P3700 400GB 750€ - 0.10€ / TBW
Intel SSD DC S3700 400GB 590€ - 0.08€ / TBW
Intel SSD DC S3710 400GB 535€ - 0.065€ / TBW

Write Amplification with ZFS should be limited due to the COW, right ?

my experience on ZFS is limited to ZFS on FreeBSD and basic ZFS based Raid-1 set up by proxmox installer


paging someone like @udo , @alexskysilk , @LnxBil or similar well versed presumed humans

 

[Alessandro 123]

Any procedure to estimate the write amplification ?

 

[Q-wulf]

Any procedure to estimate the write amplification ?

Not sure about estimating, but you can test it (once you have the hardware e.g. during your burn-in tests)
http://www.samsung.com/us/business/oem-solutions/pdfs/SSD-Sales-Presentation.pdf (page 10 and 11)

Procedure would be to measure NAND writes via Smart and then divide it by the actual Data written on the host.
This would need to be tested with the actual drives and the storage subsystem you want to use.

AFAIR (correct me if i am wrong please), these values are determined by the controllers firmware, the internal caching mechanism and most importantly the type and generation of NAND used. In other words it will be highly different for different types of SSD's