(De)Compress a file repeatedly to benchmark zlib by way of mini(un)zip

le-zlib-test.sh

#!/bin/sh
#
# Benchmark zlib performance using programs available to LibreELEC.
#

# Number of iterations to loop
COMPRESS_ITER=50
DECOMPRESS_ITER=50

# test file to compress & then decompress
CORPUS="/storage/zlib-test/Gutenberg-Mark-Twain.html"
CORPUS_FILE=$(basename "${CORPUS}")

TEMP_DIR=$(mktemp -d)

# Compression testing
for i in $(seq 0 $COMPRESS_ITER); do

    # Copy corpus to tmpfs
    cp "${CORPUS}" "${TEMP_DIR}/${CORPUS_FILE}"

    # Use first run to create zip file for decompression
    if [ $i = 0 ]; then
        # Note: minzip overwrites without confirmation
        /storage/zlib-test/minizip "${TEMP_DIR}/corpus.zip" "${TEMP_DIR}/${CORPUS_FILE}"
    else
        # Dump output to /dev/null to minimize I/O issues
        time -a -o "${TEMP_DIR}/compress_time.txt" \
            /storage/zlib-test/minizip -o /dev/null "${TEMP_DIR}/${CORPUS_FILE}"
    fi
done

# Clean up the time output
grep "real" "${TEMP_DIR}/compress_time.txt" | cut -f 2 | tr -d ' ' \
    > "${TEMP_DIR}/compress_real.txt" 

# Decompression testing
for i in $(seq 0 $DECOMPRESS_ITER); do
    if [ $i = 0 ]; then
        /storage/zlib-test/miniunz "${TEMP_DIR}/corpus.zip" -o -d "${TEMP_DIR}"
    # Dump unzipped contents to tmpfs to minimize I/O issues (/dev/null unavail to miniunz)
    else
        time -a -o "${TEMP_DIR}/decompress_time.txt" \
            /storage/zlib-test/miniunz "${TEMP_DIR}/corpus.zip" -o -d "${TEMP_DIR}"
    fi
done

# Clean up the time output
grep "real" "${TEMP_DIR}/decompress_time.txt" | cut -f 2 | tr -d ' ' \
    > "${TEMP_DIR}/decompress_real.txt" 

exit