From 0dd7b97863e6651233baa28ffb814f4cca16e8fa Mon Sep 17 00:00:00 2001 From: Joshua Levy Date: Sat, 8 Oct 2016 12:15:35 -0700 Subject: [PATCH] Fix from review. --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.md b/README.md index acc80df..2ec8791 100644 --- a/README.md +++ b/README.md @@ -1283,7 +1283,7 @@ Billing and Cost Management - 🔸**Lifetime:** There is no guarantee for the lifetime of a Spot instance. It is purely based on bidding. If anyone outbids your price, the instance is taken away. Spot is not suitable for time sensitive jobs that have strong SLA. Instances will fail based on demand for Spot at that time. AWS does not send any signal that the instance is going away, except for the fact that it is going down. That makes it hard to figure out why the instance(s) went down. - 🔹**API return data:** - The Spot price API returns Spot prices of varying granularity depending on the time range specified in the api call.E.g If the last 10 min worth of history is requested, the data is more fine grained. If the last 2 day worth of history is requested, the data is more coarser. Do not assume you will get all the data points. There **will** be skipped intervals. - ❗**Lifecycle management:** Do not attempt any fancy Spot management unless absolutely necessary. If your entire usage is only a few machines and your cost is acceptable and your failure rate is lower, do not attempt to optimize. The pain for building/maintaining it is not worth just a few hundred dollar savings. -- **Reserved instances:** allow you to get significant discounts on EC2 compute hours in return for a commitment to pay for instance hours of a specific instance type in a specific AWS region and availability zone for a pre-established time frame (1 or 3 years). Further discounts can be realized through “partial” or “all upfront” payment options. +- **Reserved Instances:** allow you to get significant discounts on EC2 compute hours in return for a commitment to pay for instance hours of a specific instance type in a specific AWS region and availability zone for a pre-established time frame (1 or 3 years). Further discounts can be realized through “partial” or “all upfront” payment options. - Consider using Reserved Instances when you can predict your longer-term compute needs and need a stronger guarantee of compute availability and continuity than the (typically cheaper) Spot market can provide. However be aware that if your architecture changes your computing needs may change as well so long term contracts can seem attractive but may turn out to be cumbersome. - Instance reservations are not tied to specific EC2 instances - they are applied at the billing level to eligible compute hours as they are consumed across all of the instances in an account. - **Hourly billing waste:** EC2 instances are [billed in instance-hours](https://aws.amazon.com/ec2/faqs/#How_will_I_be_charged_and_billed_for_my_use_of_Amazon_EC2) — rounded up to the nearest full hour! For long-lived instances, this is not a big worry, but for large transient deployments, like EMR jobs or test deployments, this can be a significant expense. Never deploy many instances and terminate them after only a few minutes. In fact, if transient instances are part of your regular processing workflow, you should put in protections or alerts to check for this kind of waste.