apache/cassandra · error · ConfigurationException

min_compress_ratio can either be 0 or greater than or equal

Error message

min_compress_ratio can either be 0 or greater than or equal to 1

What it means

CompressionParams.validate enforces that min_compress_ratio (maxCompressedLength) is either 0 (disabled) or >= 1. A ratio between 0 and 1 exclusive would claim compression below the input size, and one greater than chunkLength is internally inconsistent, so values in (0,1) are invalid.

Source

Thrown at src/java/org/apache/cassandra/schema/CompressionParams.java:472

    }

    // chunkLength must be a power of 2 because we assume so when
    // computing the chunk number from an uncompressed file offset (see
    // CompressedRandomAccessReader.decompresseChunk())
    public void validate() throws ConfigurationException
    {
        // if chunk length was not set (chunkLength == null), this is fine, default will be used
        if (chunkLength <= 0)
            throw new ConfigurationException("Invalid negative or null " + CHUNK_LENGTH_IN_KB);

        if ((chunkLength & (chunkLength - 1)) != 0)
            throw new ConfigurationException(CHUNK_LENGTH_IN_KB + " must be a power of 2");

        if (maxCompressedLength < 0)
            throw new ConfigurationException("Invalid negative " + MIN_COMPRESS_RATIO);

        if (maxCompressedLength > chunkLength && maxCompressedLength < Integer.MAX_VALUE)
            throw new ConfigurationException(MIN_COMPRESS_RATIO + " can either be 0 or greater than or equal to 1");
    }

    public Map<String, String> asMap()
    {
        if (!isEnabled())
            return Collections.singletonMap(ENABLED, "false");

        Map<String, String> options = new HashMap<>(otherOptions);
        // Use the one saved in the registry, we don't want to save the name of the service provider compressor here!
        options.put(CLASS, sstableCompressor.serializedAs().getName());
        options.put(CHUNK_LENGTH_IN_KB, chunkLengthInKB());
        if (minCompressRatio != DEFAULT_MIN_COMPRESS_RATIO)
            options.put(MIN_COMPRESS_RATIO, String.valueOf(minCompressRatio));

        return options;
    }

    public String chunkLengthInKB()

View on GitHub (pinned to 88fd0f6a0e)

Solutions

  1. Express the ratio as a value >= 1, e.g. 1.25 means compressed size must be at most 1/1.25 of the original
  2. Use 0 to disable the ratio check entirely
  3. If you meant 75% compression, write 1.33 (1/0.75) rather than 0.75

Example fix

// before
{'class': 'LZ4Compressor', 'min_compress_ratio': '0.75'}
// after
{'class': 'LZ4Compressor', 'min_compress_ratio': '1.33'}
Defensive patterns

Strategy: validation

Validate before calling

if (ratio != 0 && ratio < 1) throw new IllegalArgumentException("min_compress_ratio must be 0 or >= 1, got: " + ratio);

Try / catch

try { params.validate(); } catch (ConfigurationException e) { log.error("invalid min_compress_ratio", e); }

Prevention

When it happens

Trigger: Calling validate (via setCompressionParameters or fromMap) with min_compress_ratio between 0 and 1 (exclusive), or otherwise greater than chunkLength but below Integer.MAX_VALUE.

Common situations: Assuming the ratio is expressed as bytes-per-byte < 1 or entering a percentage like 0.75 intending 75% ratio instead of 1.75.

Understand the failure class

Background: "Invalid value" and "allowed values are" config errors: what your library rejected and how to fix it — this error's family across 41 libraries.

Related errors

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/0a423699a3eb4241. Report an issue: GitHub.