```
cat ${HADOOP_CONF_DIR}/core-site.xml | kv-pairify | grep "mapred"

mapred.maxthreads.generate.mapoutput=2 # Num threads to write map outputs
mapred.maxthreads.partition.closer=0 # Asynchronous map flushers
mapreduce.fileoutputcommitter.algorithm.version=2 # Use the latest committer version
mapreduce.job.reduce.slowstart.completedmaps=0.99 # 99% map, then reduce
mapreduce.reduce.shuffle.input.buffer.percent=0.9 # Min % buffer in RAM

	io.Writer
	fileState

	ReadFrom(io.Reader) (int64, error)
}

// Flush finishes writing the current file's block padding.
// The current file must be fully written before Flush can be called.
//
// This is unnecessary as the next call to [Writer.WriteHeader] or [Writer.Close]
// will implicitly flush out the file's padding.
func (tw *Writer) Flush() error {
	if tw.err != nil {
		return tw.err
	}

	}

	// Trailing fringe.
	copy(e.buf[:], p)
	e.nbuf = len(p)
	n += len(p)
	return
}

// Close flushes any pending output from the encoder.
// It is an error to call Write after calling Close.
func (e *encoder) Close() error {
	// If there's anything left in the buffer, flush it out
	if e.err == nil && e.nbuf > 0 {
		e.enc.Encode(e.out[:], e.buf[:e.nbuf])

func (e *Engine) Execute(s *State, file string, script *bufio.Reader, log io.Writer) (err error) {
	defer func(prev *Engine) { s.engine = prev }(s.engine)
	s.engine = e

	var sectionStart time.Time
	// endSection flushes the logs for the current section from s.log to log.
	// ok indicates whether all commands in the section succeeded.
	endSection := func(ok bool) error {
		var err error
		if sectionStart.IsZero() {

	EXTPROC                          = 0x10000
	FF1                              = 0x8000
	FFDLY                            = 0x8000
	FICLONE                          = 0x80049409
	FICLONERANGE                     = 0x8020940d
	FLUSHO                           = 0x2000
	FS_IOC_ENABLE_VERITY             = 0x80806685
	FS_IOC_GETFLAGS                  = 0x40086601
	FS_IOC_GET_ENCRYPTION_NONCE      = 0x4010661b
	FS_IOC_GET_ENCRYPTION_POLICY     = 0x800c6615

	EXTPROC                          = 0x10000
	FF1                              = 0x8000
	FFDLY                            = 0x8000
	FICLONE                          = 0x40049409
	FICLONERANGE                     = 0x4020940d
	FLUSHO                           = 0x1000
	FP_XSTATE_MAGIC2                 = 0x46505845
	FS_IOC_ENABLE_VERITY             = 0x40806685
	FS_IOC_GETFLAGS                  = 0x80046601
	FS_IOC_GET_ENCRYPTION_NONCE      = 0x8010661b

	EXTPROC                          = 0x10000
	FF1                              = 0x8000
	FFDLY                            = 0x8000
	FICLONE                          = 0x40049409
	FICLONERANGE                     = 0x4020940d
	FLUSHO                           = 0x1000
	FS_IOC_ENABLE_VERITY             = 0x40806685
	FS_IOC_GETFLAGS                  = 0x80046601
	FS_IOC_GET_ENCRYPTION_NONCE      = 0x8010661b
	FS_IOC_GET_ENCRYPTION_POLICY     = 0x400c6615

	EXTPROC                          = 0x10000
	FF1                              = 0x8000
	FFDLY                            = 0x8000
	FICLONE                          = 0x40049409
	FICLONERANGE                     = 0x4020940d
	FLUSHO                           = 0x1000
	FS_IOC_ENABLE_VERITY             = 0x40806685
	FS_IOC_GETFLAGS                  = 0x80086601
	FS_IOC_GET_ENCRYPTION_NONCE      = 0x8010661b
	FS_IOC_GET_ENCRYPTION_POLICY     = 0x400c6615

	// Is the buffer full?
	CMPL	CX, (p_wbBuf+wbBuf_end)(BX)
	JA	flush
	// Commit to the larger buffer.
	MOVL	CX, (p_wbBuf+wbBuf_next)(BX)
	// Make return value (the original next position)
	SUBL	DI, CX
	MOVL	CX, DI
	// Restore registers.
	MOVL	20(SP), CX
	MOVL	24(SP), BX
	RET

flush:
	// Save all general purpose registers since these could be

	EXTPROC                          = 0x10000
	FF1                              = 0x8000
	FFDLY                            = 0x8000
	FICLONE                          = 0x40049409
	FICLONERANGE                     = 0x4020940d
	FLUSHO                           = 0x1000
	FP_XSTATE_MAGIC2                 = 0x46505845
	FS_IOC_ENABLE_VERITY             = 0x40806685
	FS_IOC_GETFLAGS                  = 0x80086601
	FS_IOC_GET_ENCRYPTION_NONCE      = 0x8010661b