qemu/tests/benchmark-crypto-hash.c
Daniel P. Berrangé b4296d7f88 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: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-10-28 13:32:21 +01:00

70 lines
1.7 KiB
C

/*
* QEMU Crypto hash speed benchmark
*
* Copyright (c) 2017 HUAWEI TECHNOLOGIES CO., LTD.
*
* Authors:
* Longpeng(Mike) <longpeng2@huawei.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* (at your option) any later version. See the COPYING file in the
* top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu/units.h"
#include "crypto/init.h"
#include "crypto/hash.h"
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;
const size_t total = 2 * GiB;
size_t remain;
struct iovec iov;
int ret;
in = g_new0(uint8_t, chunk_size);
memset(in, g_test_rand_int(), chunk_size);
iov.iov_base = (char *)in;
iov.iov_len = chunk_size;
g_test_timer_start();
remain = total;
while (remain) {
ret = qcrypto_hash_bytesv(QCRYPTO_HASH_ALG_SHA256,
&iov, 1, &out, &out_len,
NULL);
g_assert(ret == 0);
remain -= chunk_size;
}
g_test_timer_elapsed();
g_print("sha256: ");
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);
}
int main(int argc, char **argv)
{
size_t i;
char name[64];
g_test_init(&argc, &argv, NULL);
g_assert(qcrypto_init(NULL) == 0);
for (i = 512; i <= 64 * KiB; i *= 2) {
memset(name, 0 , sizeof(name));
snprintf(name, sizeof(name), "/crypto/hash/speed-%zu", i);
g_test_add_data_func(name, (void *)i, test_hash_speed);
}
return g_test_run();
}