Iteration: 3 Total runtime: 00:00:00 WTR: 43856.27 KiB/s Transfer time: 00:00:00 IOPS: 10964.07
Iteration: 4 Total runtime: 00:00:00 WTR: 46210.64 KiB/s Transfer time: 00:00:00 IOPS: 11552.66 ...................... ......................
SATA 3T 8EA, RAID 6 # rm -rf /tmp/test && spew -i 50 -v -d --write -r -b 4096 100M ./test Iteration: 1 Total runtime: 00:00:01 WTR: 68826.83 KiB/s Transfer time: 00:00:01 IOPS: 17206.71
Iteration: 2 Total runtime: 00:00:03 WTR: 68633.67 KiB/s Transfer time: 00:00:01 IOPS: 17158.42
Iteration: 3 Total runtime: 00:00:04 WTR: 69974.56 KiB/s Transfer time: 00:00:01 IOPS: 17493.64 ...................... ......................
# spew --help Usage: spew --write|--read|--read-after-write [OPTION]... TRANSFER_SIZE[kKmMgG] FILE An I/O performance measurement and load generation tool. Writes and/or reads generated data to or from a character device, block device, or regular file.
-B, --max-buffer-size=BUFFER_SIZE Each read(2)/write(2) call uses a maximum buffer of size BUFFER_SIZE. -b, --min-buffer-size=BUFFER_SIZE Each read(2)/write(2) call uses a minimum buffer of size BUFFER_SIZE. -c, --continue-after-error Continue after data integrity errors. -d, --direct Use direct I/O. Should only be used on block device files. Not all operating systems support direct I/O -g, --generate-load Equivalent to: -v -t -P -p random -i 0. -i, --iterations=COUNT Write/read data COUNT times. If count is 0, repeats forever. -l, --logfile=LOGFILE Send log messages to LOGFILE. --no-progress Don't show progress (default). --no-rcfiles Don't use standard rcfiles. -q, --no-statistics Don't output statistics. --no-tui Don't use TUI interface. -o, --offset=OFFSET Seek to OFFSET before starting I/O. -P, --progress Show progress. -p, --pattern=PATTERN Use data pattern PATTERN when reading or writing data. -r, --random Read/Write buffers to random offsets. --raw An alias for --read-after-write. --rcfile=RCFILE Read command-line options from RCFILE. --read Read date from FILE. --read-after-write Read back data after writing to FILE. -S, --seed=SEED Use SEED for random number seed. -s, --sync Use synchronous I/O. --statistics Output statistics (default). -t, --tui Use curses-based, terminal user interface. -u, --units=UNITS Show transfer rate in UNITS units. --usage Show brief usage message and exit. -V, --version Output version information and exit. -v, --detailed-statistics Output detailed statistics. --write Write data to FILE. -?, --help Show this help and exit.
FILE Regular or device file to write data to. LOGFILE Path to a file used for logging. MAX_BUFFER_SIZE Minimum buffer size used in each read(2)/write(2) call (default is MIN_BUFFER_SIZE bytes). MAX_BUFFER_SIZE. Must be an even multiple of 512 bytes and can be specified in bytes, kibibytes(k), kilobytes(K), mebibytes(m), megabytes(M), gibibytes(g), gigabytes(G). tebibytes(t), or terabytes(T). MAX_BUFFER_SIZE defaults to MIN_BUFFER_SIZE. If MAX_BUFFER_SIZE > MIN_BUFFER_SIZE, random buffers sizes between the two limits are used. MAX_BUFFER_SIZE must be an even multiple of MIN_BUFFER_SIZE. MIN_BUFFER_SIZE Minimum buffer size used in each read(2)/write(2) call (default is 512 bytes). MIN_BUFFER_SIZE. Must be an even multiple of 512 bytes and can be specified in bytes, kibibytes(k), kilobytes(K), mebibytes(m), megabytes(M), gibibytes(g), gigabytes(G). tebibytes(t), or terabytes(T). OFFSET Position to seek to in the file before starting I/O (default is 0). OFFSET must be an even multiple of 512 bytes and can be specified in bytes, kibibytes(k), kilobytes(K), mebibytes(m), megabytes(M), gibibytes(g), gigabytes(G). tebibytes(t), or terabytes(T). PATTERN Data pattern used when writing/reading data. Available patterns are: none, zeros, ones, alt, random, numbers, and "#" (where "#" is a number between 0-255). The default pattern is "none". RCFILE Read additional command-line options from RCFILE. Other options on the command-line will override options in RCFILE. SEED Used to seed the random number generator Must be >= 1 and <= 2^32. TRANSFER_SIZE Total number of bytes to transfer (must be an even multiple of both MIN_BUFFER_SIZE and MAX_BUFFER)SIZE). TRANSFER_SIZE can be specified in bytes, kilobytes, megabytes, or gigabytes. UNITS Kibibytes(k), kilobytes(K), mebibytes(m), megabytes(M), gibibytes(g), gigabytes(G). tebibytes(t), or terabytes(T).
