rename readtest (.c not .cc)

1 files changed, 148 insertions, 0 deletions

diff --git a/tools/readtest.c b/tools/readtest.c
new file mode 100644
index 0000000000..53f559c4d3
--- /dev/null
+++ b/tools/readtest.c
@@ -0,0 +1,148 @@
+/* gcc -o readtest readtest.cc `pkg-config --cflags --libs glib-2.0` */
+
+#include <stdlib.h>
+#include <errno.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <string.h>
+#include <getopt.h>
+#include <fcntl.h>
+
+#include <glib.h>
+
+char* data = 0;
+
+int
+read_one (int fd, ssize_t sz)
+{
+
+	return 0;
+}
+
+void
+usage ()
+{
+	fprintf (stderr, "readtest [ -b BLOCKSIZE ] [ -s ] [ -D ] filename-template\n");
+}
+
+int
+main (int argc, char* argv[])
+{
+        int* files;
+	char optstring[] = "b:D";
+	uint32_t block_size = 64 * 1024 * 4;
+        bool direct = false;
+	const struct option longopts[] = {
+		{ "blocksize", 1, 0, 'b' },
+		{ "direct", 0, 0, 'D' },
+		{ 0, 0, 0, 0 }
+	};
+
+	int option_index = 0;
+	int c = 0;
+	char const * name_template = 0;
+        int flags = O_RDONLY;
+        int n = 0;
+        int nfiles = 0;
+
+	while (1) {
+		if ((c = getopt_long (argc, argv, optstring, longopts, &option_index)) == -1) {
+			break;
+		}
+
+		switch (c) {
+		case 'b':
+			block_size = atoi (optarg);
+			break;
+                case 'D':
+                        direct = true;
+                        break;
+		default:
+			usage ();
+			return 0;
+		}
+	}
+
+	if (optind < argc) {
+		name_template = argv[optind];
+	} else {
+		usage ();
+		return 1;
+	}
+        
+        while (1) {
+		char path[PATH_MAX+1];
+
+		snprintf (path, sizeof (path), name_template, n+1);
+
+		if (access (path, R_OK) != 0) {
+			break;
+		}
+
+                ++n;
+        }
+
+        if (n == 0) {
+                fprintf (stderr, "No matching files found for %s\n", name_template);
+                return 1;
+        }
+
+	printf ("Discovered %d files using %s\n", n, name_template);
+        
+        nfiles = n;
+        files = (int *) malloc (sizeof (int) * nfiles);
+
+        for (n = 0; n < nfiles; ++n) {
+
+		char path[PATH_MAX+1];
+                int fd;
+
+		snprintf (path, sizeof (path), name_template, n+1);
+
+                if ((fd = open (path, flags, 0644)) < 0) {
+			fprintf (stderr, "Could not open file #%d @ %s (%s)\n", n, path, strerror (errno));
+                        return 1;
+                }
+
+#ifdef __APPLE__
+                if (direct) {
+                        /* Apple man pages say only that it returns "a value other than -1 on success",
+                           which probably means zero, but you just can't be too careful with
+                           those guys.
+                        */
+                        if (fcntl (fd, F_NOCACHE, 1) == -1) {
+                                fprintf (stderr, "Cannot set F_NOCACHE on file #%d\n", n);
+                        }
+                }
+#endif
+
+                files[n] = fd;
+	}
+
+	data = (char*) malloc (sizeof (char) * block_size);
+	uint64_t read = 0;
+	
+	while (true) {
+		gint64 before;
+		before = g_get_monotonic_time();
+
+		for (n = 0; n < nfiles; ++n) {
+
+                        if (::read (files[n], (char*) data, block_size) != block_size) {
+                                fprintf (stderr, "read failed on file %d (%s)\n", n, strerror (errno));
+                                return -1;
+                        }
+		}
+
+		read += block_size;
+		gint64 elapsed = g_get_monotonic_time() - before;
+                double bandwidth = ((nfiles * block_size)/1048576.0) / (elapsed/1000000.0);
+		
+                printf ("BW @ %Lu %.3f seconds bandwidth %.4f MB/sec\n", read, elapsed/1000000.0, bandwidth);
+	}
+
+	return 0;
+}
+
+