Commit b4296d7f authored by Daniel P. Berrangé's avatar Daniel P. Berrangé
Browse files

tests: benchmark crypto with fixed data size, not time period 



Currently the crypto benchmarks are processing data in varying chunk
sizes, over a fixed time period. This turns out to be a terrible idea
because with small chunk sizes the overhead of checking the elapsed
time on each loop iteration masks the true performance.

Benchmarking over a fixed data size avoids the loop running any system
calls which can interfere with the performance measurements.

Before this change

Enc chunk 512 bytes 2283.47 MB/sec Dec chunk 512 bytes 2236.23 MB/sec OK
Enc chunk 4096 bytes 2744.97 MB/sec Dec chunk 4096 bytes 2614.71 MB/sec OK
Enc chunk 16384 bytes 2777.53 MB/sec Dec chunk 16384 bytes 2678.44 MB/sec OK
Enc chunk 65536 bytes 2809.34 MB/sec Dec chunk 65536 bytes 2699.47 MB/sec OK

After this change

Enc chunk 512 bytes 2058.22 MB/sec Dec chunk 512 bytes 2030.11 MB/sec OK
Enc chunk 4096 bytes 2699.27 MB/sec Dec chunk 4096 bytes 2573.78 MB/sec OK
Enc chunk 16384 bytes 2748.52 MB/sec Dec chunk 16384 bytes 2653.76 MB/sec OK
Enc chunk 65536 bytes 2814.08 MB/sec Dec chunk 65536 bytes 2712.74 MB/sec OK

The actual crypto performance hasn't changed, which shows how
significant the mis-measurement has been for small data sizes.

Reviewed-by: default avatarPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: default avatarDaniel P. Berrangé <berrange@redhat.com>
parent e2186a36

tests/benchmark-crypto-cipher.c

+14 −12
Original line number Diff line number Diff line
@@ -21,11 +21,12 @@ static void test_cipher_speed(size_t chunk_size, 
{

    QCryptoCipher *cipher;

    Error *err = NULL;

    double total = 0.0;

    uint8_t *key = NULL, *iv = NULL;

    uint8_t *plaintext = NULL, *ciphertext = NULL;

    size_t nkey;

    size_t niv;

    const size_t total = 2 * GiB;

    size_t remain;



    if (!qcrypto_cipher_supports(alg, mode)) {

        return;
@@ -58,33 +59,34 @@ static void test_cipher_speed(size_t chunk_size, 
                                      &err) == 0);



    g_test_timer_start();

    do {

    remain = total;

    while (remain) {

        g_assert(qcrypto_cipher_encrypt(cipher,

                                        plaintext,

                                        ciphertext,

                                        chunk_size,

                                        &err) == 0);

        total += chunk_size;

    } while (g_test_timer_elapsed() < 1.0);

        remain -= chunk_size;

    }

    g_test_timer_elapsed();



    total /= MiB;

    g_print("Enc chunk %zu bytes ", chunk_size);

    g_print("%.2f MB/sec ", total / g_test_timer_last());

    g_print("%.2f MB/sec ", (double)total / MiB / g_test_timer_last());



    total = 0.0;

    g_test_timer_start();

    do {

    remain = total;

    while (remain) {

        g_assert(qcrypto_cipher_decrypt(cipher,

                                        plaintext,

                                        ciphertext,

                                        chunk_size,

                                        &err) == 0);

        total += chunk_size;

    } while (g_test_timer_elapsed() < 1.0);

        remain -= chunk_size;

    }

    g_test_timer_elapsed();



    total /= MiB;

    g_print("Dec chunk %zu bytes ", chunk_size);

    g_print("%.2f MB/sec ", total / g_test_timer_last());

    g_print("%.2f MB/sec ", (double)total / MiB / g_test_timer_last());



    qcrypto_cipher_free(cipher);

    g_free(plaintext);

tests/benchmark-crypto-hash.c

+9 −8
Original line number Diff line number Diff line
@@ -20,7 +20,8 @@ static void test_hash_speed(const void *opaque) 
    size_t chunk_size = (size_t)opaque;

    uint8_t *in = NULL, *out = NULL;

    size_t out_len = 0;

    double total = 0.0;

    const size_t total = 2 * GiB;

    size_t remain;

    struct iovec iov;

    int ret;
@@ -31,20 +32,20 @@ static void test_hash_speed(const void *opaque) 
    iov.iov_len = chunk_size;



    g_test_timer_start();

    do {

    remain = total;

    while (remain) {

        ret = qcrypto_hash_bytesv(QCRYPTO_HASH_ALG_SHA256,

                                  &iov, 1, &out, &out_len,

                                  NULL);

        g_assert(ret == 0);



        total += chunk_size;

    } while (g_test_timer_elapsed() < 5.0);

        remain -= chunk_size;

    }

    g_test_timer_elapsed();



    total /= MiB;

    g_print("sha256: ");

    g_print("Testing chunk_size %zu bytes ", chunk_size);

    g_print("done: %.2f MB in %.2f secs: ", total, g_test_timer_last());

    g_print("%.2f MB/sec\n", total / g_test_timer_last());

    g_print("Hash %zu GB chunk size %zu bytes ", total / GiB, chunk_size);

    g_print("%.2f MB/sec ", (double)total / MiB / g_test_timer_last());



    g_free(out);

    g_free(in);