{"record":{"id":"5102291c2212dfce","repo":"vectordotdev/vector","slug":"default-maximum-data-file-size-should-never-be-gre","errorCode":null,"errorMessage":"Default maximum data file size should never be greater than 2^64 bytes.","messagePattern":"Default maximum data file size should never be greater than 2\\^64 bytes\\.","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"info","filePath":"lib/vector-buffers/src/variants/disk_v2/common.rs","lineNumber":324,"sourceCode":"        FS2: Filesystem,\n    {\n        DiskBufferConfigBuilder {\n            data_dir: self.data_dir,\n            max_buffer_size: self.max_buffer_size,\n            max_data_file_size: self.max_data_file_size,\n            max_record_size: self.max_record_size,\n            write_buffer_size: self.write_buffer_size,\n            flush_interval: self.flush_interval,\n            filesystem,\n        }\n    }\n\n    /// Consumes this builder and constructs a `DiskBufferConfig`.\n    pub fn build(self) -> Result<DiskBufferConfig<FS>, BuildError> {\n        let max_buffer_size = self.max_buffer_size.unwrap_or(u64::MAX);\n        let max_data_file_size = self.max_data_file_size.unwrap_or_else(|| {\n            u64::try_from(DEFAULT_MAX_DATA_FILE_SIZE)\n                .expect(\"Default maximum data file size should never be greater than 2^64 bytes.\")\n        });\n        let max_record_size = self.max_record_size.unwrap_or(DEFAULT_MAX_RECORD_SIZE);\n        let write_buffer_size = self.write_buffer_size.unwrap_or(DEFAULT_WRITE_BUFFER_SIZE);\n        let flush_interval = self.flush_interval.unwrap_or(DEFAULT_FLUSH_INTERVAL);\n        let filesystem = self.filesystem;\n\n        // Validate the input parameters.\n        if max_data_file_size == 0 {\n            return Err(BuildError::InvalidParameter {\n                param_name: \"max_data_file_size\",\n                reason: \"cannot be zero\".to_string(),\n            });\n        }\n\n        let data_file_size_mechanical_limit = get_maximum_data_file_size();\n        if max_data_file_size > data_file_size_mechanical_limit {\n            return Err(BuildError::InvalidParameter {\n                param_name: \"max_data_file_size\",","sourceCodeStart":306,"sourceCodeEnd":342,"githubUrl":"https://github.com/vectordotdev/vector/blob/3708c39b12a93212ed8b8d7510b4cc7769cb5864/lib/vector-buffers/src/variants/disk_v2/common.rs#L306-L342","documentation":"When building a DiskBufferConfig without an explicit `max_data_file_size`, Vector converts the DEFAULT_MAX_DATA_FILE_SIZE constant (128 MiB, defined in common.rs) from `usize` to `u64`. The constant is fixed and fits trivially, so the expect is an assertion about build-time values only; it cannot fire for any user configuration.","triggerScenarios":"u64::try_from(DEFAULT_MAX_DATA_FILE_SIZE) failing — impossible since the constant is 128 * 1024 * 1024 and `usize` is at least 32-bit; only a hypothetical >64-bit `usize` target could trip it.","commonSituations":"None; the value is a compile-time literal.","solutions":["No action possible or needed; report upstream if it ever appears"],"exampleFix":null,"handlingStrategy":"validation","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":["Nothing to guard: the default is a 128 MiB compile-time constant","Setting an explicit max_data_file_size bypasses this line entirely if you want determinism"],"tags":["rust","vector","disk-buffer","invariant","integer-conversion","panic"],"backgroundTag":"integer-width-conversion-panic","analyzedSha":"3708c39b12a93212ed8b8d7510b4cc7769cb5864","analyzedAt":"2026-08-20T07:02:18.786Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-08T20:17:18.057Z"}