Lifespan: Up to 6 petabytes of Writes

Seagate is calling the Pulsar a 5 year drive. If you are absolutely dying to know how many writes you can do to the drive, there is a way of finding out.

Remember the sustained write figures from earlier? Seagate guarantees that you’ll be able to run at those sustained write rates for a period of 5 years before the drive dies.

I’ve done the math below:

Drive Sustained 4KB Random Write IOPS KB Written per Second # of Seconds in 5 Years (1825 days) Total Writes in 5 Years
200GB 10,500 42000 157,680,000 seconds 6167 TB
100GB 5300 21200 3113 TB
50GB 2600 10400 1527 TB


At 1527TB (or 1.49 petabytes) of random 4KB writes in a 5 year period, the 50GB Pulsar has a worse lifespan than Intel’s X25-E (the 64GB drive is specced at 2 petabytes of lifetime random writes).

The 200GB drive however can allegedly withstand over 6100TB (6 petabytes) of random writes before it goes to SSD heaven.

With no standardized method of testing or verifying any of these claims, we can’t do much more than take Seagate’s word for it. Given Seagate’s reputation in the industry, I’d expect that its word is worth it.

Final Words

There’s little more to say about Pulsar than what I’ve already mentioned. Seagate is finally getting in the game and, at least on paper, Pulsar appears to be in the class of Intel’s X25-E.

If Seagate can deliver on its promises, this should be good. Currently the enterprise SSD market is occupied by Intel, Samsung and a bunch of other contenders with unproven track records. Using Indilinx drives in a server environment is very tempting, but also potentially dangerous. There isn’t sufficient data out there today to say how long their drives will last under constant random writes. I tend to believe Seagate when they commit to Pulsar being a 5 year drive capable of over 6PB of random writes.

Pricing is another major unknown, but I’d expect the drives to be no cheaper than Intel’s X25-E: at least $11 per GB.

Even more exciting is the promise of consumer level SSDs from Seagate, possibly as early as 2010. Western Digital is next, whom I expect to join the race in 2010 as well. Once all of the major HDD players are in the race, we’ll see some real competition in both the high end and mainstream client SSD markets.

Seagate Goes Light on the Details


View All Comments

  • juzz86 - Tuesday, December 8, 2009 - link

    I just picked up on something the author said which I've never seen before but often wondered. If I were to format my 80GB X25-M G2 with a 70GB partition, would I see better performance having that extra 4.5GB set aside as spare area? Is this just a relatively simple way of getting even better speeds? Or am I barking up the wrong tree? Reply
  • GullLars - Tuesday, December 8, 2009 - link

    If you have TRIM firmware and use the standard W7 drivers so the command actually hits the drive, you will see no difference as long as the ammount of used area is the same. With trim any free area is effectivly spare area. If you however run a RAID or use controllers or drivers that don't forward trim, you will see better _sustained_ write numbers with a smaller partition. In order for the drive to make use of this unpartitioned space, you either have to partition the drive when brand new, or directly after a Secure Erase.

    In reply to the article. It seems to me from the performance numbers that Segate might have fused its own IP with Intels and made it's own 8-channel controller. It would make perfect sense, and explain why the performance numbers of x25-E 64GB and Pulsar 50GB are so simelar.

    It makes me a bit sad that Samsung didn't go for a 16-channel design on the higher capasity drives that will use 16 NAND chips or more, since this basically limits the random read IOPS and peak write IOPS. These 8-channel drives will have to go head to head with SandForce's SF1500, wich are 16-channel SLC drives targeting the same market.

    BTW, i think all new high-performance SSD released in 2010 should start using SATA or SAS 6Gbps as standard to help accelerate adoption rates and remove an unnecessary botleneck (seq read).
  • jimhsu - Tuesday, December 8, 2009 - link

    The distinction between peak and sustained performance is highly interesting. Performance profiles for today's SSDs (post JMicron) are highly complex, and depend on free space, recent writes, TRIM/GC availability, and any concurrent operations. For example, a recurring issue seems to be IO stalling when a large sequential write operation is taking place (i.e. copying a huge file to the SSD while trying to use the drive normally).

    Might Seagate have found a workaround to this? All things considered though, I would much rather see a max IO latency figure.
  • Proteusza - Tuesday, December 8, 2009 - link

    Avoid the Streissand Effect (and its related effects) at all costs. Whenever a company withholds information or seems like it is withholding information, it makes them look bad.

    I'm not saying Seagate has anything to hide, but if it were more upfront with its technology and what forms part of the Pulsar, it would be in a stronger marketing position. Hiding information just doesnt do it for me, but I suppose I've been spoilt by Intel and AMD lately, which generally reveal almost everything about their new hardware.
  • Jovec - Tuesday, December 8, 2009 - link

    This site is big enough now to demand a minimum set of specs and information if the product company wants to be reviewed. Reply
  • chen4119 - Tuesday, December 8, 2009 - link

    What about STEC Mach8 SSD drive? They've qualified for EMC, IBM, and SUN enterprise storage systems and they did really well this year. How do they compare to Intel SSD drives or Indinix controller drives? Just wondering how come there are no mentions of STEC in this blog. Reply
  • mckirkus - Tuesday, December 8, 2009 - link

    They're super high end enterprise drives. It's the same reason you don't see RAMSANs in WD Raptor reviews. Reply
  • yuhong - Tuesday, December 8, 2009 - link

    Yea, back when Bill Watkins was CEO of Seagate, he promised that Seagate would sue SSD makers, and later indeed Seagate tried to sue STEC. That lawsuit was dropped in Feb 2009. Reply
  • gfody - Tuesday, December 8, 2009 - link

    +1, I found out about STEC while evaluating an EMC SAN. Apparently they have their own controller and use MLC. Where's Anand with the scoop? Reply
  • pcfxer - Tuesday, December 8, 2009 - link

    ugh EMC. A company that brags about firmware updates that don't require rebooting then release a CRITICAL firmware update that requires some....REBOOTING. As it turned out, that firmware (applied days before christmas) decided to choke and puke on MY CHRISTMAS DAY! EMC, never again.

    Let me save you the pain my friend, look else where. Thecus...iron storage, ixSystems, ANYONE but EMC.

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