Add a very basic test of direct disk writing speed.

1 files changed, 114 insertions, 0 deletions

diff --git a/hacks/direct_disk_speed_test.cc b/hacks/direct_disk_speed_test.cc
new file mode 100644
index 000000000..0e20e2fdd
--- /dev/null
+++ b/hacks/direct_disk_speed_test.cc
@@ -0,0 +1,114 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+int test_posix(int block_size, int blocks, int gap, int rdisk, int nocache)
+{
+	struct timeval start;
+	gettimeofday(&start, NULL);
+
+	int f = -1;
+	if (rdisk) {
+		f = open("/dev/rdisk3", O_RDWR);
+     	} else {
+		f = open("/dev/disk3", O_RDWR);
+	}
+        if (f == -1) {
+		printf("open failed.\n");
+		return -1;
+	}
+
+	fcntl(f, F_NOCACHE, nocache);
+
+	void* buffer = malloc(block_size);
+	if (!buffer) {
+		printf("malloc failed.\n");
+		return -1;
+	}
+
+	for (int i = 0; i < blocks; ++i) {
+		write(f, buffer, block_size);
+		if (gap > 0) {
+			lseek(f, gap, SEEK_CUR);
+		}
+	}
+
+	close(f);
+
+	struct timeval end;
+	gettimeofday(&end, NULL);
+	float duration = ((end.tv_sec + end.tv_usec / 1e6) - (start.tv_sec + start.tv_usec / 1e6));
+	printf("POSIX: block_size=%d blocks=%d gap=%d rdisk=%d nocache=%d time=%f\n", block_size, blocks, gap, rdisk, nocache, duration);
+	return 0;
+}
+
+
+int test_stdio(int block_size, int blocks, int gap, int rdisk)
+{
+	struct timeval start;
+	gettimeofday(&start, NULL);
+
+	FILE* f = NULL;
+	if (rdisk) {
+		f = fopen("/dev/rdisk3", "r+b");
+     	} else {
+		f = fopen("/dev/disk3", "r+b");
+	}
+        if (!f) {
+		printf("fopen failed.\n");
+		return -1;
+	}
+
+	setbuf(f, 0);
+
+	void* buffer = malloc(block_size);
+	if (!buffer) {
+		printf("malloc failed.\n");
+		return -1;
+	}
+
+	for (int i = 0; i < blocks; ++i) {
+		fwrite(buffer, block_size, 1, f);
+		if (gap > 0) {
+			fseek(f, gap, SEEK_CUR);
+		}
+	}
+
+	fclose(f);
+
+	struct timeval end;
+	gettimeofday(&end, NULL);
+	float duration = ((end.tv_sec + end.tv_usec / 1e6) - (start.tv_sec + start.tv_usec / 1e6));
+	printf("STDIO: block_size=%d blocks=%d gap=%d rdisk=%d time=%f\n", block_size, blocks, gap, rdisk, duration);
+	return 0;
+}
+
+
+int main()
+{
+	for (int i = 0; i < 2; i++) {
+/*
+		test_posix(4096, 4096, 0, i);
+		test_posix(4096, 4096, 0, i);
+		test_posix(8192, 2048, 0, i);
+		test_posix(4096, 4096, 4096, i);
+		test_posix(4096, 4096, 65536, i);
+		test_posix(8192, 2048, 65536, i);
+		test_posix(16384, 1024, 65536, i);
+*/
+		for (int j = 0; j < 2; j++) {
+			// test_posix(4096, 262144, 0, i, j);
+			// test_posix(8192, 131072, 0, i, j);
+			// test_posix(16384, 65536, 0, i, j);
+			test_posix(32768, 32768, 0, i, j);
+			test_posix(65536, 16384, 0, i, j);
+			test_posix(131072, 8192, 0, i, j);
+			test_posix(262144, 4096, 0, i, j);
+			test_posix(524288, 2048, 0, i, j);
+		}
+	}
+}
+