more docs

Author: ErinWeisbart

documentation/DCP-documentation/costs.md

@@ -16,7 +16,11 @@ Simple spot fleet configurations can be minimized by:
 
 1) Optimize `MACHINE_TYPE` and `EBS_VOL_SIZE` based on the actual memory and harddrive needs of your run.
 2) When possible, mount your S3 bucket using S3FS so that you can set `DOWNLOAD_FILES = 'False'` to not incur file egress costs.
+See [Step 1 Configuration](step_1_configuration.md) for more information.
+Data egress charges range for various reasons including traversing AWS regions and/or AWS availability zones but are [often $0.08–$0.12 per GB](https://aws.amazon.com/blogs/apn/aws-data-transfer-charges-for-server-and-serverless-architectures/).
 3) Set `ASSIGN_IP = 'False'` so that you don't pay for IPv4 addresses per EC2 instance in your spot fleet.
+Public IPv4 costs are minimal ([$0.005/IP/hour as of February 1, 2024](https://aws.amazon.com/blogs/aws/new-aws-public-ipv4-address-charge-public-ip-insights/)) but there is no need to incur even this minimal cost unless you have a specific need for it.
+See [Step 1 Configuration](step_1_configuration.md) for more information.
 
 Spot fleet costs can be minimized/stopped in multiple ways:
 

documentation/DCP-documentation/step_1_configuration.md

@@ -49,15 +49,18 @@ Distinct clusters for each job are not necessary, but if you're running multiple
 * **MACHINE_PRICE:** How much you're willing to pay per hour for each machine launched.
 AWS has a handy [price history tracker](https://console.aws.amazon.com/ec2sp/v1/spot/home) you can use to make a reasonable estimate of how much to bid.
 If your jobs complete quickly and/or you don't need the data immediately you can reduce your bid accordingly; jobs that may take many hours to finish or that you need results from immediately may justify a higher bid.
+See also [AWS on-demand pricing](https://aws.amazon.com/ec2/pricing/on-demand/) to compare the cost savings of using spot fleets.
 * **EBS_VOL_SIZE:** The size of the temporary hard drive associated with each EC2 instance in GB.
 The minimum allowed is 22.
 If you have multiple Dockers running per machine, each Docker will have access to (EBS_VOL_SIZE/TASKS_PER_MACHINE)- 2 GB of space.
 * **DOWNLOAD_FILES:** Whether or not to download the image files to the EBS volume before processing, as opposed to accessing them all from S3FS.
 This typically requires a larger EBS volume (depending on the size of your image sets, and how many sets are processed per group), but avoids occasional issues with S3FS that can crop up on longer runs.
+By default, DCP uses S3FS to mount the S3 `SOURCE_BUCKET` as a pseudo-file system on each EC2 instance in your spot fleet to avoid file download.
+If you are unable to mount the `SOURCE_BUCKET` (perhaps because of a permissions issue) you should proceed with `DOWNLOAD_FILES = 'True'`.
 * **ASSIGN_IP:** Whether or not to assign an a public IPv4 address to each instance in the spot fleet.
 If set to 'False' will overwrite whatever is in the Fleet file.
 If set to 'True' will respect whatever is in the Fleet file.
-Distributed-CellProfiler originally defaulted to assign an IP address to each instance so that one could connect to the instance for troubleshooting but that need has been obviated by the level of logging currently in DCP.
+Distributed-CellProfiler originally defaulted to assign an IP address to each instance so that one could connect to the instance for troubleshooting but that need has been mostly obviated by the level of logging currently in DCP.
 
 ***