littlefs/benches/bench_mtree.toml

# Bench our high-level metadata tree in the core of littlefs
after = ['bench_rbyd', 'bench_btree']

# maximize lookahead buffer, we don't actually gc so we only get one pass
# of the disk for these tests
defines.LOOKAHEAD_SIZE = 'BLOCK_COUNT / 8'

[cases.bench_mtree_lookup]
defines.N = [8, 16, 32, 64, 128, 256, 1024]
# 0 = in-order
# 1 = reversed-order
# 2 = random-order
defines.ORDER = [0, 1, 2]
defines.SEED = 42
in = 'lfs.c'
code = '''
    uint32_t prng = SEED;
    const char *alphas = "abcdefghijklmnopqrstuvwxyz";

    lfs_t lfs;
    lfsr_format(&lfs, CFG) => 0;
    lfsr_mount(&lfs, CFG) => 0;
    lfs_alloc_ack(&lfs);

    // create an mtree with N entries
    for (lfs_size_t i = 0; i < N; i++) {
        // choose an mid
        lfs_ssize_t mid
                = lfsr_mtree_weight(&lfs) == 0 ? -1
                : (ORDER == 0) ? (lfs_ssize_t)(lfsr_mtree_weight(&lfs)-1)
                : (ORDER == 1) ? 0
                : (lfs_ssize_t)(BENCH_PRNG(&prng) % lfsr_mtree_weight(&lfs));
        // fetch mdir
        lfsr_mdir_t mdir;
        lfsr_mtree_lookup(&lfs, mid, &mdir) => 0;

        // choose rid
        lfs_ssize_t rid
                = (ORDER == 0) ? lfsr_mdir_weight(&mdir)
                : (ORDER == 1) ? 0
                : BENCH_PRNG(&prng) % (lfsr_mdir_weight(&mdir)+1);

        // create an entry
        lfsr_mdir_commit(&lfs, &mdir, &rid, LFSR_ATTRS(
                LFSR_ATTR(rid, INLINED, +1, &alphas[i % 26], 1))) => 0;
    }

    // bench lookup
    BENCH_START();
    // choose an mid
    lfs_ssize_t mid
            = lfsr_mtree_weight(&lfs) == 0 ? -1
            : (lfs_ssize_t)(BENCH_PRNG(&prng) % lfsr_mtree_weight(&lfs));
    // fetch mdir
    lfsr_mdir_t mdir;
    lfsr_mtree_lookup(&lfs, mid, &mdir) => 0;

    // choose rid
    lfs_ssize_t rid = BENCH_PRNG(&prng) % lfsr_mdir_weight(&mdir);

    // lookup
    uint8_t buffer[4];
    lfsr_mdir_get(&lfs, &mdir, rid, LFSR_TAG_INLINED, buffer, 4) => 1;
    BENCH_STOP();

    lfsr_unmount(&lfs) => 0;
'''

[cases.bench_mtree_commit]
defines.N = [8, 16, 32, 64, 128, 256, 1024]
# 0 = in-order
# 1 = reversed-order
# 2 = random-order
defines.ORDER = [0, 1, 2]
defines.SEED = 42
defines.AMORTIZED = false
in = 'lfs.c'
code = '''
    uint32_t prng = SEED;
    const char *alphas = "abcdefghijklmnopqrstuvwxyz";

    lfs_t lfs;
    lfsr_format(&lfs, CFG) => 0;
    lfsr_mount(&lfs, CFG) => 0;
    lfs_alloc_ack(&lfs);

    // create an mtree with N entries
    if (AMORTIZED) {
        BENCH_START();
    }
    for (lfs_size_t i = 0; i < N; i++) {
        // choose an mid
        lfs_ssize_t mid
                = lfsr_mtree_weight(&lfs) == 0 ? -1
                : (ORDER == 0) ? (lfs_ssize_t)(lfsr_mtree_weight(&lfs)-1)
                : (ORDER == 1) ? 0
                : (lfs_ssize_t)(BENCH_PRNG(&prng) % lfsr_mtree_weight(&lfs));
        // fetch mdir
        lfsr_mdir_t mdir;
        lfsr_mtree_lookup(&lfs, mid, &mdir) => 0;

        // choose rid
        lfs_ssize_t rid
                = (ORDER == 0) ? lfsr_mdir_weight(&mdir)
                : (ORDER == 1) ? 0
                : BENCH_PRNG(&prng) % (lfsr_mdir_weight(&mdir)+1);

        // create an entry
        lfsr_mdir_commit(&lfs, &mdir, &rid, LFSR_ATTRS(
                LFSR_ATTR(rid, INLINED, +1, &alphas[i % 26], 1))) => 0;
    }

    // bench commit
    if (!AMORTIZED) {
        BENCH_START();
    }
    // choose an mid
    lfs_ssize_t mid
            = lfsr_mtree_weight(&lfs) == 0 ? -1
            : (ORDER == 0) ? (lfs_ssize_t)(lfsr_mtree_weight(&lfs)-1)
            : (ORDER == 1) ? 0
            : (lfs_ssize_t)(BENCH_PRNG(&prng) % lfsr_mtree_weight(&lfs));
    // fetch mdir
    lfsr_mdir_t mdir;
    lfsr_mtree_lookup(&lfs, mid, &mdir) => 0;

    // choose rid
    lfs_ssize_t rid
            = (ORDER == 0) ? lfsr_mdir_weight(&mdir)
            : (ORDER == 1) ? 0
            : BENCH_PRNG(&prng) % (lfsr_mdir_weight(&mdir)+1);

    // create an entry
    lfsr_mdir_commit(&lfs, &mdir, &rid, LFSR_ATTRS(
            LFSR_ATTR(rid, INLINED, +1, "C", 1))) => 0;
    BENCH_STOP();

    lfsr_unmount(&lfs) => 0;
'''

[cases.bench_mtree_traversal]
defines.N = [8, 16, 32, 64, 128, 256, 1024]
# 0 = in-order
# 1 = reversed-order
# 2 = random-order
defines.ORDER = [0, 1, 2]
defines.SEED = 42
defines.VALIDATE = [false, true]
in = 'lfs.c'
code = '''
    uint32_t prng = SEED;
    const char *alphas = "abcdefghijklmnopqrstuvwxyz";

    lfs_t lfs;
    lfsr_format(&lfs, CFG) => 0;
    lfsr_mount(&lfs, CFG) => 0;
    lfs_alloc_ack(&lfs);

    // create an mtree with N entries
    for (lfs_size_t i = 0; i < N; i++) {
        // choose an mid
        lfs_ssize_t mid
                = lfsr_mtree_weight(&lfs) == 0 ? -1
                : (ORDER == 0) ? (lfs_ssize_t)(lfsr_mtree_weight(&lfs)-1)
                : (ORDER == 1) ? 0
                : (lfs_ssize_t)(BENCH_PRNG(&prng) % lfsr_mtree_weight(&lfs));
        // fetch mdir
        lfsr_mdir_t mdir;
        lfsr_mtree_lookup(&lfs, mid, &mdir) => 0;

        // choose rid
        lfs_ssize_t rid
                = (ORDER == 0) ? lfsr_mdir_weight(&mdir)
                : (ORDER == 1) ? 0
                : BENCH_PRNG(&prng) % (lfsr_mdir_weight(&mdir)+1);

        // create an entry
        lfsr_mdir_commit(&lfs, &mdir, &rid, LFSR_ATTRS(
                LFSR_ATTR(rid, INLINED, +1, &alphas[i % 26], 1))) => 0;
    }

    // traverse the mtree
    BENCH_START();
    lfsr_mtree_traversal_t traversal = LFSR_MTREE_TRAVERSAL_INIT(
            VALIDATE ? LFSR_MTREE_TRAVERSAL_VALIDATE : 0);

    for (lfs_block_t i = 0;; i++) {
        // a bit hacky, but this catches infinite loops
        assert(i < 2*(1+N));

        lfs_size_t mid_;
        lfsr_tag_t tag_;
        lfsr_data_t data_;
        int err = lfsr_mtree_traversal_next(&lfs, &traversal,
                &mid_, &tag_, &data_);
        assert(!err || err == LFS_ERR_NOENT);
        if (err == LFS_ERR_NOENT) {
            break;
        }

        assert(tag_ == LFSR_TAG_BTREE || tag_ == LFSR_TAG_MDIR);
    }
    BENCH_STOP();

    lfsr_unmount(&lfs) => 0;
'''