symlink operation not supported on 'latest_log_dir'

[barrh]

python3 distiller/examples/classifier_compression/compress_classifier.py --arch=[...] --workers=[...] --compress=examples/agp-pruning/[...].yaml --batch-size=[...] --epochs=[..] --lr [...] --num-best-scores=[..] imagenet -o=[...]

Log file for this run: [...]/2019.02.17-120315/2019.02.17-120315.log
Traceback (most recent call last):
File "distiller/examples/classifier_compression/compress_classifier.py", line 748, in
main()
File "distiller/examples/classifier_compression/compress_classifier.py", line 97, in main
msglogger = apputils.config_pylogger(os.path.join(script_dir, 'logging.conf'), args.name, args.output_dir)
File "distiller/apputils/execution_env.py", line 134, in config_pylogger
os.symlink(logdir, "latest_log_dir")
OSError: [Errno 95] Operation not supported: '[...]/2019.02.17-120315' -> 'latest_log_dir'

Commenting out that part seems to avoid that issue completely: https://github.com/NervanaSystems/distiller/blame/master/apputils/execution_env.py#L126-L135

[barrh]

Probably not an issue by itself, but I didn't expect that the directory will get named that way:
When specified the experiment name (read, --name=NAME), the result is something like this: NAME___2019.02.17-120734

[barrh]

I found the rootcause: symlinks aren't always possible to generate.
I had tried to call compress_classifier.py from a mounted nfs drive, and sent the logs to a local drive.

[nzmora]

Re: #157 (comment)
This has been the intended behavior since the introduction of this feature.

Cheers
Neta