Jacob Wilkins (5/26/2015)
andrew gothard (5/26/2015)
... Obviously this is an issue with any infrastructure, would it be more of an issue with this type of kit though?It is probably somewhat more of an issue with the Nimble than with a more traditional array at a similar price point, just because the more traditional competitor will likely be using more than 12 HDDs.
Unfortunately, as with so many other things it comes down to a tradeoff. With the Nimble, your baseline performance will likely be significantly better than with similarly priced traditional array, but worst-case performance could be worse than with the traditional array.
Having said that, at least in the several environments we've used Nimbles, they've been an improvement over the previous (often more expensive) arrays, sometimes even when they have run into the cache churn issue.
Also, at this point Nimble has more options than when this was an issue for us. I think now you can add capacity shelves to get more HDDs, as well as all-flash shelves to get more cache.
All in all, a Nimble's probably a good decision. At the very least, it should be at least as good overall as (and probably noticeably superior to) anything else in a similar price range. Obviously going with something all-flash like a Pure would win the performance contest, but well, that's comparing apples and gold-plated, diamond-studded oranges 🙂
Yes - there are apparently some new bells and whistles. 300 series and up, up to 6 secondary shelves can be attached. One additional SSD shelf can be attached IIRC up to 16, added in batches of 4. One rather nice thing, certainly for our use patterns, is aggressive caching - which is somewhere between standard and pinning. When a new record's added it stays 'sticky' in cache for a while - so stays in, say, for a day beflore being flushed if it's not read.
Works very well for us, patient comes in, stuff's generated, people access it as they progress through the encounter. Encounter completes and then it's not likely to be accessed until they next see us.
For me, the structure itself works - in principle - better for Database work than the more standard SAN architectures which are IMO still more file server focussed. Although, RAID 6 ... meh. Although can see the argument for triple parity for data integrity.
I'm a DBA.
I'm not paid to solve problems. I'm paid to prevent them.