[Bug] ConfigStore.store() extremely slow

[Jasha10]

🐛 Bug

Description

Calling ConfigStore.store(name=..., node=MyDataclass) is extremely slow with certain dataclasses.

(tmp) jbss@rig1:~/mwe$ cat mwe.py
from hydra.core.config_store import ConfigStore
import time
from dataclasses import dataclass
from omegaconf import OmegaConf

cs = ConfigStore.instance()

@dataclass
class Config:
    iterp: str = "${long_string1xxx}_${long_string2xxx:${a_key}}"       # cs.store takes ~27s

t0 = time.time()
cs.store(name="config_schema", node=Config)
t1 = time.time()
print(f"Config Elapsed time = {t1-t0}")

(tmp) jbss@rig1:~/mwe$ python mwe.py
Config Elapsed time = 26.96069574356079

That's almost 27 seconds for the call to cs.store!
I did an ablation study to find that the length of long_string1xxx and long_string2xxx do matter; longer strings are slower.

@dataclass
class Config:
    iterp: str = "${long_string1xxx}_${long_string2xxx:${a_key}}"       # cs.store takes ~27s

    # ablation:

    # iterp: str = "${short1}_${short2:${a_key}}"                            # cs.store takes ~0.0002 seconds
    # iterp: str = "${long_string1}_${long_string2:${a_key}}"                # cs.store takes ~0.5s
    # iterp: str = "${long_string1x}_${long_string2x:${a_key}}"              # cs.store takes ~1.9s
    # iterp: str = "${long_string1xx}_${long_string2xx:${a_key}}"            # cs.store takes ~6.9s

    # iterp: str = "${long_string1xxx}_${short:${a_key}}"                    # cs.store takes ~0.07s
    # iterp: str = "${short}_${long_string2xxx:${a_key}}"                    # cs.store takes ~0.06s
    # iterp: str = "${short1}_${short2:${a_very_very_very_very_long_key}}"   # cs.store takes ~0.01 seconds

    # iterp: str = "${long_string2xxx:${a_key}}"                             # cs.store takes ~0.01s
    # iterp: str = "_${long_string2xxx:${a_key}}"                            # cs.store takes ~0.01s
    # iterp: str = "${long_string1xxx}_"                                     # cs.store takes ~0.0003s
    # iterp: str = "${long_string1xxx}"                                      # cs.store takes ~0.0003s
    # iterp: str = "${long_string1xxx}_${long_string2xxx}"                   # cs.store takes ~0.0003s
    # iterp: str = "${long_string1xxx}_${long_string2xxx:a_key}"             # cs.store takes ~0.003s

System information

Using the latest omegaconf and hydra installed from master branch.

Python 3.8.5 (default, Sep  4 2020, 07:30:14)
[GCC 7.3.0] :: Anaconda, Inc. on linux
omegaconf.__version__='2.1.0dev23'
hydra.__version__='1.1.0dev5'

• Operating system : Ubuntu 18.04

Edit: I was not able to reproduce this with hydra/omegaconf downloaded from pip, only with the latest development versions of hydra/omegaconf.

[omry]

Thanks.
Can you narrow it down to a repro using OmegaConf only?

[Jasha10]

Filed against OmegaConf: omry/omegaconf#622