Re: Interesting read on SCM upending software and hardware architecture

On Mon, Jan 18, 2016 at 1:44 AM, David Fetter <david@fetter.org> wrote:
> On Sun, Jan 17, 2016 at 11:13:33PM -0500, Bruce Momjian wrote:
>> On Thu, Jan  7, 2016 at 02:30:06PM -0600, Jim Nasby wrote:
>> > https://queue.acm.org/detail.cfm?id=2874238 discusses how modern
>> > Storage Class Memory (SCM), such as PCIe SSD and NVDIMMs are
>> > completely upending every assumption made about storage. To put
>> > this in perspective, you can now see storage latency that is
>> > practically on-par with things like lock acquisition[1].
>>
>> How is this different from Fusion I/O devices, which have been
>> around for years?
>
> Price.
>
> As these things come down in price, it'll start being more and more
> reasonable to treat rotating media as exotic.

<rant>People keep predicting the death of spinning media, but I think
it's not happening to anywhere near as fast as that people think.
Yes, I'm writing this on a laptop with an SSD, and my personal laptop
also has an SSD, but their immediate predecessors did not, and these
are fairly expensive laptops.  And most customers I talk to are still
using spinning disks.  Meanwhile, main memory is getting so large that
even pretty significant databases can be entirely RAM-cached.  So I
tend to think that this is a lot less exciting than people who are not
me seem to think.</rant>

Now that having been said, I will not complain if vast quantities of
low-latency, high-bandwidth, non-volatile storage become available at
bargain prices.  And it very well may - eventually.  But I'm not quite
ready to break out the ticker tape just yet.  I think it will be a
while.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company