We recently covered Seagate's XNUMXTB IronWolf Pro, and now the XNUMXTB EXOS is here to check it out.
According to the manufacturers, Seagate EXOS 20TB is aimed at those with cloud data centers, massively scaling data center applications, mass storage, and enterprise NAS systems. Where the IronWolf Pro was intended for commercial and enterprise NAS to meet the needs of Creative Pro and medium to large businesses.
Since they look virtually identical from the outside, does the EXOS 20TB simply wear a different hat than its IronWolf Pro sibling?
Award
The Seagate EXOS 20TB retails for €XNUMX on Amazon.com and €XNUMX on Amazon.co.uk, but we found it a bit more affordable while we shopped.
Compared to the largest predecessor drive in this range, the 317.50TB EXOS comes at a premium, as we found the XNUMXTB model for €XNUMX (€XNUMX) at multiple online retailers.
This represents a seventy percent increase in cost for two TB, or an eleven percent increase in capacity.
However, the cost of the channel depends on the demand, and since the twenty TB EXOS is new, the demand is high. We expect the cost of this coin to drop once production exceeds demand later in the year.
It should be noted that the official MSRP of the twenty TB EXOS is €649,99, so the market cost of these devices already feels a strong gravitational pull.
Integrated
If they didn't have labels, we wouldn't be able to tell the XNUMXTB IronWolf Pro and EXOS drives apart.
To the casual observer, it is the exact same XNUMXg block of metal that houses a XNUMXrpm CMR (usual magnetic recording) hard drive with ten XNUMXTB platters and twenty heads, running in a sealed helium atmosphere. of factory.
All differences are internal, and due to the lack of a weight difference, any differences that do exist are likely to be firmware based rather than physical.
Seagate has tailored EXOS for use in data centers, where high-capacity RAID arrays are used for big data applications, distributed file systems, and disaster recovery platforms.
It uses a Hyperspace SATA model, developed for large data transfers with low latency, and the internal digital sensors adjust to thermal changes to offer unbeatable performance.
Where the 5TB IronWolf Pro delivered a Mean Time Between Failure (MTBF) of XNUMX million hours and annual workload is XNUMXTB, the XNUMXTB EXOS exceeds those levels with an MTBF of XNUMX million. of hours and an annual workload of five hundred and fifty TB.
That translates to a 5-year warranty with a TBW of XNUMX TB, compared to XNUMX TBW on the IronWolf Pro.
This is music to the ears of those who service and maintain data center arrays, as the possibility of drive failure and the array being critical is not a scenario they like.
Another difference is that the twenty TB EXOS is free on both SATA and SAS connections, while the IronWolf Pro is SATA only.
SATA EXOS comes with either Standard or SED FastFormat, and the SAS model adds SED-FIPS to those options.
For those using SAS to connect arrays to multiple servers for failover functionality, this could be another reason to go with EXOS as it doubles the potential lanes from one to two on each and every drive.
SAS functionality aside, does the Enterprise service customer pay a bit more for their possible peace of mind, or is there more to EXOS than this basic equation?
Performance
REFERENCES
Here's how the Seagate EXOS 20TB SATA drive performed in our benchmark tests:
CrystalDiskMark: two hundred and eighty-nine with seven MB/s (read); 295,75 MB/s (write) Atto: 281,32 MB/s (read, 256 MB); 275,27MB/s (write, 256MB)
PCMark10 Data Reader Score: 861
In terms of operational speed, we had a hard time separating the 20TB IronWolf Pro and EXOS in our benchmark.
Both could read and write at almost 285MB/s in most tests, a 10% improvement that may be directly related to the platter and the additional heads this drive has over the 18TB model.
The numbers for EXOS were a bit higher, but within what we consider to be variance.
But unlike the IronWolf Pro, the 20TB design shows no improvement in operational power demand over the 18TB models, with the SAS models using an additional 0,4W over the idle SATA versions.
The maximum power of EXOS can consume 9,4 W over SATA and 9,8 W over SAS, but typical demands are 6,4 W and 6,8 W, less than the 7,7 W average required by IronWolf.
For data center operations, lower power consumption is good because less is converted to heat.
Resistance
We had concerns about the IronWolf Pro 20TB and its 300TB per year workload. These are taken care of to some extent by the 550TB per year workload offered by the 20TB EXOS.
However, if you haven't read this review, we should mention that unlike SSDs, the workload of a physical hard drive is calculated based on read and write, and not just write.
Most NAND cell damage occurs during random writes to an SSD, with relatively minor wear and tear during reads.
On a physical hard drive, such as EXOS, wear occurs every time the platters spin, regardless of any reading or writing that accompanies that movement.
Doing the same calculations we did for IronWolf Pro, taking the 2750TB limit over 5 years and dividing by capacity, we ended up with a total transferred bytes of 137,5TB per TB of disk capacity.
That's hardly surprising compared to an unbranded NAND SSD, though it's a lot better than the 75TB of workload transfer offered by the IronWolf Pro.
One issue we noticed while covering the IronWolf is that for the sanity of those who maintain the data center, regular inspections of the arrays are carried out to ensure that the integrity of the data stored there is good.
Reading the entire drive for an integrity test once a week would use up to 1040 TB per year, nearly double the yearly limit, and that's without any operational use.
To stay within this limit and be useful, integrity tests need to be reduced in frequency, probably to once a month.
As drives get even bigger, that could become the limiting factor, not the innovative ways drive manufacturers find to squeeze more bytes out of them.
Competitors
Western Digital offers the UltraStar DC HC560 as a data center offering, priced at €449,99 (€699,99), respectively for the SE security option.
The UltraStar DC HC560 is the only direct competitor to the 20TB EXOS, as Toshiba has yet to release a XNUMXTB drive.
Rumor has it that by the end of the year, Toshiba will introduce a 26TB ten-platter drive based on microwave-assisted switching technology (MAS-MAMR), to be followed by a 30TB 11-platter model next year.
But until official announcements and availability are made public, it's EXOS or UltraStar for those who want 20TB data center drives.
final verdict
We like the increased workload of the EXOS and for that reason would choose them for use in a critical bay over the IronWolf Pro. But are these workload numbers enough?
If you want 20TB drives in an array, here's what you can expect. Western Digital UltraStar DC HC560 has the same workload numbers, so the alternatives come with the same caveat.
Obviously Seagate and Western Digital have done the math and come to the same conclusion about these devices and how much use they are likely to sustain before they need to be replaced.
For the customer, the choice is between the largest disks available, allowing for the largest arrays possible, or to spread the workload across less expensive disks with potentially higher levels of redundancy.
The expression “between a rock and a hard place” seems the most appropriate for this dilemma.
We'd choose this drive over the IronWolf Pro for an array, but choosing this capacity over smaller, more numerous drives is a rather difficult choice.