elastic/elasticsearch · error · IllegalArgumentException

Negative memory size specified in [{option}]

Error message

Negative memory size specified in [{option}]

What it means

Thrown by OverridableSystemMemoryInfo.availableSystemMemory() when the -Des.total_memory_bytes system property is set to a negative long. This property overrides ES's detected system memory for heap sizing; a negative value is nonsensical.

Source

Thrown at distribution/tools/server-cli/src/main/java/org/elasticsearch/server/cli/OverridableSystemMemoryInfo.java:39

    private final List<String> userDefinedJvmOptions;
    private final SystemMemoryInfo fallbackSystemMemoryInfo;

    public OverridableSystemMemoryInfo(final List<String> userDefinedJvmOptions, SystemMemoryInfo fallbackSystemMemoryInfo) {
        this.userDefinedJvmOptions = Objects.requireNonNull(userDefinedJvmOptions);
        this.fallbackSystemMemoryInfo = Objects.requireNonNull(fallbackSystemMemoryInfo);
    }

    @Override
    public long availableSystemMemory() {

        return userDefinedJvmOptions.stream()
            .filter(option -> option.startsWith("-Des.total_memory_bytes="))
            .map(totalMemoryBytesOption -> {
                try {
                    long bytes = Long.parseLong(totalMemoryBytesOption.split("=", 2)[1]);
                    if (bytes < 0) {
                        throw new IllegalArgumentException("Negative memory size specified in [" + totalMemoryBytesOption + "]");
                    }
                    return bytes;
                } catch (NumberFormatException e) {
                    throw new IllegalArgumentException("Unable to parse number of bytes from [" + totalMemoryBytesOption + "]", e);
                }
            })
            .reduce((previous, current) -> current) // this is effectively findLast(), so that ES_JAVA_OPTS overrides jvm.options
            .orElse(fallbackSystemMemoryInfo.availableSystemMemory());
    }
}

View on GitHub (pinned to db6a809a66)

Solutions

1. Set -Des.total_memory_bytes to a positive value in bytes (e.g. 8589934592 for 8 GiB).
2. If you do not need the override, remove the -Des.total_memory_bytes entry entirely and let ES auto-detect.
3. Double-check any script/template that computes the value for arithmetic bugs.

Example fix

# ES_JAVA_OPTS — before
ES_JAVA_OPTS="-Des.total_memory_bytes=-8589934592"

# after
ES_JAVA_OPTS="-Des.total_memory_bytes=8589934592"

userDefinedJvmOptions.stream()
    .filter(o -> o.startsWith("-Des.total_memory_bytes="))
    .forEach(o -> {
        long v = Long.parseLong(o.split("=", 2)[1]);
        if (v < 0) throw new IllegalArgumentException("total_memory_bytes must be >= 0: " + o);
    });

When it happens

Trigger: Passing -Des.total_memory_bytes=-1 (or any negative number) via ES_JAVA_OPTS or jvm.options.

Common situations: Typo when overriding memory for testing; a script computing the value that underflows to negative; misunderstanding the unit (bytes, not MB/GB).

Related errors

• Unable to parse number of bytes from [${totalMemoryBytesOpti
• Invalid jvm argument `{}` configure as systemProperty instea
• starting java failed with [%d] output: %s error: %s
• 78
• unexpected exception creating MessageDigest instance for [{}

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/8a9ac9960c3612f7. Report an issue: GitHub.