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@codeflash-ai codeflash-ai bot commented Nov 13, 2025

📄 6% (0.06x) speedup for is_zero_gpu_space in gradio/utils.py

⏱️ Runtime : 2.83 milliseconds 2.66 milliseconds (best of 61 runs)

📝 Explanation and details

The optimization replaces os.getenv("SPACES_ZERO_GPU") with os.environ.get("SPACES_ZERO_GPU"), achieving a 6% speedup by eliminating one function call layer.

What changed:

  • os.getenv() internally calls os.environ.get(), so using os.environ.get() directly removes the intermediate wrapper function call
  • This reduces the call stack depth from 2 levels to 1 level per invocation

Why it's faster:

  • Eliminates function call overhead - each call to os.getenv() adds the cost of an additional Python function dispatch
  • With 4,576 hits in the profiler, this micro-optimization compounds significantly
  • Per-hit time improved from 2,501.1ns to 2,277.3ns (about 224ns saved per call)

Impact on workloads:
The function reference shows is_zero_gpu_space() is called in Blocks.queue() - a core Gradio component setup method. This means the optimization benefits:

  • Every Gradio app initialization that uses queueing
  • Zero GPU space detection during app startup/configuration
  • The improvement is most noticeable when this function is called frequently, as shown in test cases with loops (5-6% improvement in bulk operations)

Test case performance:
The optimization shows consistent 15-28% improvements across individual test cases, with the best gains when the environment variable is unset (17-20% faster) or set to non-"true" values. Large-scale tests with 1000+ iterations show 5-6% improvements, indicating the optimization scales well with usage frequency.

Correctness verification report:

Test Status
⚙️ Existing Unit Tests 🔘 None Found
🌀 Generated Regression Tests 4394 Passed
⏪ Replay Tests 182 Passed
🔎 Concolic Coverage Tests 🔘 None Found
📊 Tests Coverage 100.0%
🌀 Generated Regression Tests and Runtime
import os

# imports
import pytest  # used for our unit tests
from gradio.utils import is_zero_gpu_space

# unit tests

# --- Basic Test Cases ---

def test_true_string_returns_true():
    """SPACES_ZERO_GPU is 'true': should return True."""
    os.environ["SPACES_ZERO_GPU"] = "true"
    codeflash_output = is_zero_gpu_space() # 1.86μs -> 1.46μs (27.9% faster)

def test_false_string_returns_false():
    """SPACES_ZERO_GPU is 'false': should return False."""
    os.environ["SPACES_ZERO_GPU"] = "false"
    codeflash_output = is_zero_gpu_space() # 1.68μs -> 1.45μs (15.7% faster)

def test_none_env_returns_false():
    """SPACES_ZERO_GPU is not set: should return False."""
    if "SPACES_ZERO_GPU" in os.environ:
        del os.environ["SPACES_ZERO_GPU"]
    codeflash_output = is_zero_gpu_space() # 2.21μs -> 1.88μs (17.4% faster)

# --- Edge Test Cases ---

@pytest.mark.parametrize("value", [
    "",  # empty string
    "True",  # capitalized
    "TRUE",  # all caps
    "tRuE",  # mixed case
    "1",  # numeric string
    "0",  # numeric string
    "yes",  # non-boolean string
    "false ",  # trailing space
    " false",  # leading space
    " true",  # leading space
    "true ",  # trailing space
    "tru",  # partial match
    "falsey",  # similar word
])
def test_non_true_strings_return_false(value):
    """SPACES_ZERO_GPU set to various non-'true' values: should return False."""
    os.environ["SPACES_ZERO_GPU"] = value
    codeflash_output = is_zero_gpu_space() # 22.0μs -> 18.7μs (18.0% faster)

def test_env_set_to_none_returns_false():
    """SPACES_ZERO_GPU set to None (via os.environ): should return False."""
    # os.environ only accepts str, but simulate by deleting key
    if "SPACES_ZERO_GPU" in os.environ:
        del os.environ["SPACES_ZERO_GPU"]
    codeflash_output = is_zero_gpu_space() # 2.28μs -> 1.94μs (17.9% faster)

def test_env_set_to_whitespace_returns_false():
    """SPACES_ZERO_GPU set to whitespace: should return False."""
    os.environ["SPACES_ZERO_GPU"] = "   "
    codeflash_output = is_zero_gpu_space() # 1.62μs -> 1.40μs (15.6% faster)

def test_env_set_to_unexpected_type_returns_false():
    """SPACES_ZERO_GPU set to a non-str type (simulate via str()): should return False."""
    os.environ["SPACES_ZERO_GPU"] = str(None)
    codeflash_output = is_zero_gpu_space() # 1.71μs -> 1.37μs (24.5% faster)

def test_env_set_to_special_characters_returns_false():
    """SPACES_ZERO_GPU set to special characters: should return False."""
    os.environ["SPACES_ZERO_GPU"] = "@!#"
    codeflash_output = is_zero_gpu_space() # 1.61μs -> 1.40μs (15.3% faster)

# --- Large Scale Test Cases ---

def test_many_env_changes_consistency():
    """Rapidly change SPACES_ZERO_GPU between 'true' and 'false', check consistency."""
    for i in range(100):
        os.environ["SPACES_ZERO_GPU"] = "true"
        codeflash_output = is_zero_gpu_space() # 62.0μs -> 57.1μs (8.59% faster)
        os.environ["SPACES_ZERO_GPU"] = "false"
        codeflash_output = is_zero_gpu_space()

def test_bulk_false_values():
    """Test a large number of different false-like values."""
    false_values = ["false", "False", "FALSE", "0", "no", "n", "off", "disabled", "not_true", "tru", "t", "f", "none", "null", "nil", "undefined", "", " ", "\t", "\n"]
    for val in false_values:
        os.environ["SPACES_ZERO_GPU"] = val
        codeflash_output = is_zero_gpu_space() # 13.5μs -> 12.3μs (10.4% faster)

def test_bulk_true_values():
    """Test that only exact 'true' returns True, all others return False."""
    # Only 'true' should return True
    os.environ["SPACES_ZERO_GPU"] = "true"
    codeflash_output = is_zero_gpu_space() # 1.54μs -> 1.34μs (14.9% faster)
    # All other variants should return False
    variants = ["True", "TRUE", "tRuE", "true ", " true", "true\n", "true\t"]
    for val in variants:
        os.environ["SPACES_ZERO_GPU"] = val
        codeflash_output = is_zero_gpu_space() # 4.49μs -> 4.20μs (6.83% faster)

def test_env_unset_many_times():
    """Unset SPACES_ZERO_GPU repeatedly, ensure always False."""
    for _ in range(100):
        if "SPACES_ZERO_GPU" in os.environ:
            del os.environ["SPACES_ZERO_GPU"]
        codeflash_output = is_zero_gpu_space() # 72.5μs -> 67.8μs (7.00% faster)
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
import os

# imports
import pytest  # used for our unit tests
from gradio.utils import is_zero_gpu_space

# unit tests

@pytest.mark.parametrize(
    "env_value,expected",
    [
        # Basic Test Cases: Environment variable set to "true"
        ("true", True),  # canonical case, should return True
        # Basic Test Cases: Environment variable set to "false"
        ("false", False),  # canonical case, should return False
        # Basic Test Cases: Environment variable unset
        (None, False),  # unset means None, should return False
    ]
)
def test_basic_is_zero_gpu_space(monkeypatch, env_value, expected):
    """
    Basic test cases for is_zero_gpu_space.
    - "true" should return True
    - "false" should return False
    - Unset should return False
    """
    # Set or unset the environment variable
    if env_value is not None:
        monkeypatch.setenv("SPACES_ZERO_GPU", env_value)
    else:
        monkeypatch.delenv("SPACES_ZERO_GPU", raising=False)
    # Assert the expected result
    codeflash_output = is_zero_gpu_space() # 5.12μs -> 4.16μs (23.1% faster)

@pytest.mark.parametrize(
    "env_value",
    [
        "TRUE",      # uppercase
        "True",      # capitalized
        "tRuE",      # mixed case
        "1",         # numeric true-ish
        "yes",       # yes as true-ish
        "false",     # valid false
        "FALSE",     # uppercase false
        "False",     # capitalized false
        "0",         # numeric false-ish
        "no",        # no as false-ish
        "random",    # random string
        "",          # empty string
        "  true",    # leading space
        "true  ",    # trailing space
        " true ",    # leading/trailing space
        "tru",       # substring
        "tr ue",     # space in string
        "truetrue",  # repeated
        "true,false",# comma separated
    ]
)
def test_edge_is_zero_gpu_space(monkeypatch, env_value):
    """
    Edge test cases for is_zero_gpu_space.
    - Only exact "true" (lowercase) should return True.
    - Everything else should return False.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", env_value)
    # Only "true" should return True, all others False
    expected = env_value == "true"
    codeflash_output = is_zero_gpu_space() # 30.6μs -> 26.0μs (17.7% faster)

def test_env_var_removed(monkeypatch):
    """
    Edge case: Environment variable is removed after being set.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true")
    codeflash_output = is_zero_gpu_space() # 1.62μs -> 1.34μs (20.6% faster)
    monkeypatch.delenv("SPACES_ZERO_GPU")
    codeflash_output = is_zero_gpu_space() # 1.16μs -> 1.10μs (4.98% faster)

def test_env_var_set_to_none(monkeypatch):
    """
    Edge case: Environment variable set to None (should behave as unset).
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true")
    codeflash_output = is_zero_gpu_space() # 1.58μs -> 1.35μs (17.7% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", None)
    # os.environ will have a string "None", not NoneType
    codeflash_output = is_zero_gpu_space() # 831ns -> 733ns (13.4% faster)

def test_env_var_set_to_empty_string(monkeypatch):
    """
    Edge case: Environment variable set to empty string.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "")
    codeflash_output = is_zero_gpu_space() # 1.50μs -> 1.28μs (17.0% faster)

def test_env_var_unset(monkeypatch):
    """
    Edge case: Environment variable never set.
    """
    monkeypatch.delenv("SPACES_ZERO_GPU", raising=False)
    codeflash_output = is_zero_gpu_space() # 1.84μs -> 1.53μs (19.7% faster)

def test_env_var_multiple_times(monkeypatch):
    """
    Edge case: Environment variable is set and unset multiple times.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "false")
    codeflash_output = is_zero_gpu_space() # 1.61μs -> 1.37μs (17.2% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", "true")
    codeflash_output = is_zero_gpu_space() # 857ns -> 713ns (20.2% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", "TRUE")
    codeflash_output = is_zero_gpu_space() # 640ns -> 617ns (3.73% faster)
    monkeypatch.delenv("SPACES_ZERO_GPU", raising=False)
    codeflash_output = is_zero_gpu_space() # 1.10μs -> 1.03μs (7.60% faster)

def test_env_var_with_whitespace(monkeypatch):
    """
    Edge case: Environment variable is set with whitespace.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", " true ")
    codeflash_output = is_zero_gpu_space() # 1.60μs -> 1.37μs (16.3% faster)

def test_env_var_with_special_characters(monkeypatch):
    """
    Edge case: Environment variable is set with special characters.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true!")
    codeflash_output = is_zero_gpu_space() # 1.58μs -> 1.34μs (17.8% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", "@true")
    codeflash_output = is_zero_gpu_space() # 745ns -> 676ns (10.2% faster)

def test_env_var_with_long_string(monkeypatch):
    """
    Edge case: Environment variable is set to a long string containing 'true'.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "x"*500 + "true" + "y"*500)
    codeflash_output = is_zero_gpu_space() # 1.94μs -> 1.80μs (7.62% faster)

def test_env_var_with_unicode(monkeypatch):
    """
    Edge case: Environment variable is set to a unicode string.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "trüe")
    codeflash_output = is_zero_gpu_space() # 2.32μs -> 2.07μs (12.3% faster)

def test_env_var_with_newline(monkeypatch):
    """
    Edge case: Environment variable is set to "true\n".
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true\n")
    codeflash_output = is_zero_gpu_space() # 1.63μs -> 1.34μs (21.3% faster)

def test_env_var_with_tab(monkeypatch):
    """
    Edge case: Environment variable is set to "true\t".
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true\t")
    codeflash_output = is_zero_gpu_space() # 1.60μs -> 1.33μs (20.4% faster)

def test_env_var_with_multiple_env_vars(monkeypatch):
    """
    Edge case: Other environment variables are set, but only SPACES_ZERO_GPU matters.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true")
    monkeypatch.setenv("OTHER_ENV_VAR", "false")
    codeflash_output = is_zero_gpu_space() # 1.65μs -> 1.40μs (17.9% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", "false")
    codeflash_output = is_zero_gpu_space() # 784ns -> 742ns (5.66% faster)

def test_env_var_case_sensitive(monkeypatch):
    """
    Edge case: Case sensitivity is enforced.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "TRUE")
    codeflash_output = is_zero_gpu_space() # 1.58μs -> 1.34μs (17.2% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", "True")
    codeflash_output = is_zero_gpu_space() # 776ns -> 665ns (16.7% faster)

def test_env_var_boolean(monkeypatch):
    """
    Edge case: Environment variable is set to a boolean value (should be string).
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", str(True))
    codeflash_output = is_zero_gpu_space() # 1.60μs -> 1.35μs (17.9% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", str(False))
    codeflash_output = is_zero_gpu_space() # 819ns -> 778ns (5.27% faster)

def test_env_var_numeric(monkeypatch):
    """
    Edge case: Environment variable is set to numeric value.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "1")
    codeflash_output = is_zero_gpu_space() # 1.53μs -> 1.25μs (22.5% faster)
    monkeypatch.setenv("SPACES_ZERO_GPU", "0")
    codeflash_output = is_zero_gpu_space() # 746ns -> 641ns (16.4% faster)

def test_env_var_large_scale_true(monkeypatch):
    """
    Large Scale Test Case: Environment variable set to "true" in a loop of 1000 checks.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "true")
    for _ in range(1000):
        codeflash_output = is_zero_gpu_space() # 572μs -> 542μs (5.51% faster)

def test_env_var_large_scale_false(monkeypatch):
    """
    Large Scale Test Case: Environment variable set to "false" in a loop of 1000 checks.
    """
    monkeypatch.setenv("SPACES_ZERO_GPU", "false")
    for _ in range(1000):
        codeflash_output = is_zero_gpu_space() # 569μs -> 539μs (5.52% faster)

def test_env_var_large_scale_random(monkeypatch):
    """
    Large Scale Test Case: Environment variable set to random strings in a loop of 1000 checks.
    Only "true" should return True.
    """
    import random
    import string
    values = ["true", "false", "TRUE", "True", "1", "0", "", "yes", "no"] + [
        ''.join(random.choices(string.ascii_letters, k=10)) for _ in range(990)
    ]
    # Ensure "true" is present at least once
    values[0] = "true"
    for value in values:
        monkeypatch.setenv("SPACES_ZERO_GPU", value)
        expected = value == "true"
        codeflash_output = is_zero_gpu_space() # 602μs -> 567μs (6.13% faster)

def test_env_var_large_scale_toggle(monkeypatch):
    """
    Large Scale Test Case: Toggle environment variable between "true" and "false" 1000 times.
    """
    for i in range(1000):
        monkeypatch.setenv("SPACES_ZERO_GPU", "true" if i % 2 == 0 else "false")
        expected = (i % 2 == 0)
        codeflash_output = is_zero_gpu_space() # 615μs -> 578μs (6.41% faster)
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
⏪ Replay Tests and Runtime
Test File::Test Function Original ⏱️ Optimized ⏱️ Speedup
test_pytest_testtest_components_py_testcomponentstest_audio_py_testcomponentstest_file_py_testcomponentst__replay_test_0.py::test_gradio_utils_is_zero_gpu_space 149μs 141μs 5.51%✅

To edit these changes git checkout codeflash/optimize-is_zero_gpu_space-mhwzx9lj and push.

Codeflash Static Badge

The optimization replaces `os.getenv("SPACES_ZERO_GPU")` with `os.environ.get("SPACES_ZERO_GPU")`, achieving a **6% speedup** by eliminating one function call layer.

**What changed:**
- `os.getenv()` internally calls `os.environ.get()`, so using `os.environ.get()` directly removes the intermediate wrapper function call
- This reduces the call stack depth from 2 levels to 1 level per invocation

**Why it's faster:**
- Eliminates function call overhead - each call to `os.getenv()` adds the cost of an additional Python function dispatch
- With 4,576 hits in the profiler, this micro-optimization compounds significantly
- Per-hit time improved from 2,501.1ns to 2,277.3ns (about 224ns saved per call)

**Impact on workloads:**
The function reference shows `is_zero_gpu_space()` is called in `Blocks.queue()` - a core Gradio component setup method. This means the optimization benefits:
- Every Gradio app initialization that uses queueing
- Zero GPU space detection during app startup/configuration
- The improvement is most noticeable when this function is called frequently, as shown in test cases with loops (5-6% improvement in bulk operations)

**Test case performance:**
The optimization shows consistent 15-28% improvements across individual test cases, with the best gains when the environment variable is unset (17-20% faster) or set to non-"true" values. Large-scale tests with 1000+ iterations show 5-6% improvements, indicating the optimization scales well with usage frequency.
@codeflash-ai codeflash-ai bot requested a review from mashraf-222 November 13, 2025 05:36
@codeflash-ai codeflash-ai bot added ⚡️ codeflash Optimization PR opened by Codeflash AI 🎯 Quality: High Optimization Quality according to Codeflash labels Nov 13, 2025
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