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New Interactive Partition on Cori Now Available!

May 1, 2017 by Rebecca Hartman-Baker

In response to user feedback about long waits for debugging, NERSC has deployed experimental functionality to support medium-length interactive work on Cori. Users will be able to submit interactive jobs for as many as 20 nodes for up to 4 hours and get access to them within one minute. To ensure this queue is available to anyone who wants to use it, a user is limited to only one job at a time, and a repo is limited to a total of 20 nodes of any type (Haswell AND KNL).

We have reserved 192 Haswell nodes and 192 KNL nodes for this capability. We're still experimenting with this service, so we appreciate your patience as well as your constructive feedback while we get the wrinkles ironed out. Our goal is that jobs submitted to the interactive partition will either start or be rejected within one minute (with a preference for "start"), so we will be monitoring the load and will make adjustments in response to the level of usage. Please use this limited resource only for situations where interactive use and fast feedback are required.

To run an interactive job on Cori, simply use "salloc" as normal, with the addition of "--qos=interactive" to indicate the interactive partition. You can use the usual "-C haswell" or "-C KNL" flags to select node type, as well as all other regular salloc flags ("-t", etc.). Currently only quad cache mode is available on the KNL node type.

For more information, please see the Cori running interactive jobs webpage. Please submit a ticket to the consultants, via,, or, with any feedback or questions.