[StarCluster] Spot instances

[Joydeep Sen Sarma]

afaik:

- yes - spot instances can be taken away anytime (when, presumably,
the bid price is not high enough)

- from what i have seen - bidding at around the on-demand instance
price (or maybe just a bit higher) would be good enough strategy to a)
minimize the odds of having nodes taken away b) get some general
reduction in cost (since most times the spot price is 30-40% lower
than on-demand price)

  the higher you bid above the spot price - the less, obviously, the
odds of the nodes getting taken away. at the same time - the bidding
seems to be like a second-price auction - so higher bids, in general,
don't translate into higher spends.

there have been some random price spikes (hundreds of dollars in one
case i think) - so the general advice is not bid some astronomical
number.


On Wed, Aug 29, 2012 at 3:00 PM, Ed Morris <ecm200 at gmail.com> wrote:
> Hi.
>
> I was wondering if anyone could help describe how Star Cluster behaves with
> spot instances.
>
> If I specify a bid price at a certain level, and then the spot price exceeds
> that whilst say, a parallel compute job is using those resources, what will
> happen? Will the nodes be shut down as the bid price has been exceeded?
>
> Or is the bid price simply used to start the nodes when the price reduces to
> a certain cost level or below?
>
> I am running parallel compute jobs that take a few days to complete a single
> job, and hence termination of compute nodes during the job would cause
> issues.
>
> However, I would very much like to gain access to the reduced costs of spot
> prices, with the obvious chance that I could pay more if the spot price rose
> above the fixed price.
>
> Any help would be greatly appreciated.
>
> Kind regards,
>
> Ed Morris.
>
> --
> Ed Morris
> ------------------------------------------------
> email: ecm200 at gmail.com
> phone:
>
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