PBJ Runtimes and Models

The PBJ (Powered by Jupyter) Runtime enables a wide variety of language kernels to be run as CML workloads. Model workloads are currently only supported for Python and R kernels.

A new library, cml, is added to Runtime based Python and R workloads automatically and includes mostly the same functionality as the old cdsw library.

In non-PBJ Runtimes, you could point to a Python or R function and run it as a model. PBJ Runtimes open up the possibilities for users to create their own Runtimes and places few restrictions on how to do that. PBJ technology utilizes the Jupyter kernelgateway to communicate with language kernels and aims to be language independent in the future.

Migrating from the cdsw to cml library

PBJ Runtimes currently includes two supported languages, Python and R. There are new function wrappers or decorators, described below, that must be used in order to allow previously written model code to function in a PBJ Runtime. It is important to note that these support decorators or wrappers are transparent, that is, they have no effect, in non-PBJ workloads and non-model workloads.

Table 1. Python names
CDSW CML
call_model models_v1.call_model
- models_v1.cml_model
get_auth utils_v1.get_auth
track_file Removed
model_metrics Replaced by models_v1.cml_model(metrics=True)
read_metrics metrics_v1.read_metrics
track_metric metrics_v1.track_metric
track_delayed_metrics metrics_v1.track_delayed_metrics
track_aggregate_metrics metrics_v1.track_aggregate_metrics
launch_workers workers_v1.launch_workers
list_workers workers_v1.list_workers
stop_workers workers_v1.stop_workers
await_workers workers_v1.await_workers
Table 2. R names
CDSW CML
html Planned for future release
iframe Planned for future release
markdown Planned for future release
display.help Planned for future release
code Planned for future release
image Planned for future release
get.auth get.auth
launch.workers launch.workers
stop.workers stop.workers
list.workers list.workers
await.workers await.workers
track.metric Removed
track.file Removed
- cml_model

Library availability

In CML, The cdsw and s libraries are available in different runtime and engine types.

Runtime / Engine type Library availablility
Legacy Engine cdsw
Classic Runtime cdsw, cml
PBJ Runtime cml