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50af12dbd

Eric Andersen

2003-08-06

FAILED Duration: 96s

Subject

Sync hdparm -t and -T options with hdparm-5.3, which seems to produce sensible results,

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

miscutils/hdparm.c +69 -66

miscutils/hdparm.c+69 -66

@@ -1023,11 +1023,14 @@ static void identify (uint16_t id_supplied, const char devname)

	#define VERSION "v5.4"

-	#undef DO_FLUSHCACHE /* under construction: force cache flush on -W0 */
-	#define TIMING_BUF_MB 2
+	#define TIMING_MB 64
+	#define TIMING_BUF_MB 1
	#define TIMING_BUF_BYTES (TIMING_BUF_MB * 1024 * 1024)
+	#define TIMING_BUF_COUNT (timing_MB / TIMING_BUF_MB)
	#define BUFCACHE_FACTOR 2

+	#undef DO_FLUSHCACHE /* under construction: force cache flush on -W0 */
+
	static int verbose = 0, get_identity = 0, get_geom = 0, noisy = 1, quiet = 0;
	static int flagcount = 0, do_flush = 0, is_scsi_hd = 0, is_xt_hd = 0;
	static int do_ctimings, do_timings = 0;
@@ -1303,13 +1306,15 @@ static int read_big_block (int fd, char *buf)
	return 0;
	}

-	static void time_cache (int fd)
+	static double correction = 0.0;
+
+	void time_cache (int fd)
	{
+	int i;
	char *buf;
	struct itimerval e1, e2;
	int shmid;
-	double elapsed, elapsed2;
-	unsigned int iterations, total_MB;
+	int timing_MB = TIMING_MB;

	if ((shmid = shmget(IPC_PRIVATE, TIMING_BUF_BYTES, 0600)) == -1) {
	bb_perror_msg ("could not allocate sharedmem buf");
@@ -1332,7 +1337,12 @@ static void time_cache (int fd)
	sync();
	sleep(3);

-	/*
+	/* Calculate a correction factor for the basic
+	* overhead of doing a read() from the buffer cache.
+	* To do this, we read the data once to "cache it" and
+	* to force full preallocation of our timing buffer,
+	* and then we re-read it 10 times while timing it.
+	*
	* getitimer() is used rather than gettimeofday() because
	* it is much more consistent (on my machine, at least).
	*/
@@ -1346,42 +1356,34 @@ static void time_cache (int fd)
	sync();
	sleep(1);

-	/* Now do the timing */
-	iterations = 0;
+	/* Time re-reading from the buffer-cache */
	getitimer(ITIMER_REAL, &e1);
-	do {
-	++iterations;
-	if (seek_to_zero (fd) \|\| read_big_block (fd, buf))
-	goto quit;
-	getitimer(ITIMER_REAL, &e2);
-	elapsed = (e1.it_value.tv_sec - e2.it_value.tv_sec)
-	+ ((e1.it_value.tv_usec - e2.it_value.tv_usec) / 1000000.0);
-	} while (elapsed < 2.0);
-	total_MB = iterations * TIMING_BUF_MB;
-
-	elapsed = (e1.it_value.tv_sec - e2.it_value.tv_sec)
+	for (i = (BUFCACHE_FACTOR * TIMING_BUF_COUNT) ; i > 0; --i) {
+	if (seek_to_zero (fd)) goto quit;
+	if (read_big_block (fd, buf)) goto quit;
+	}
+	getitimer(ITIMER_REAL, &e2);
+	correction = (e1.it_value.tv_sec - e2.it_value.tv_sec)
	+ ((e1.it_value.tv_usec - e2.it_value.tv_usec) / 1000000.0);

-	/* Now remove the lseek() and getitimer() overheads from the elapsed time */
+	/* Now remove the lseek() from the correction factor */
	getitimer(ITIMER_REAL, &e1);
-	do {
-	if (seek_to_zero (fd))
-	goto quit;
-	getitimer(ITIMER_REAL, &e2);
-	elapsed2 = (e1.it_value.tv_sec - e2.it_value.tv_sec)
-	+ ((e1.it_value.tv_usec - e2.it_value.tv_usec) / 1000000.0);
-	} while (--iterations);
-
-	elapsed -= elapsed2;
-
-	if ((BUFCACHE_FACTOR * total_MB) >= elapsed) /* more than 1MB/s */
-	printf("%3u MB in %5.2f seconds = %6.2f MB/sec\n",
-	(BUFCACHE_FACTOR * total_MB), elapsed,
-	(BUFCACHE_FACTOR * total_MB) / elapsed);
+	for (i = (BUFCACHE_FACTOR * TIMING_BUF_COUNT) ; i > 0; --i) {
+	if (seek_to_zero (fd)) goto quit;
+	}
+	getitimer(ITIMER_REAL, &e2);
+	correction -= (e1.it_value.tv_sec - e2.it_value.tv_sec)
+	+ ((e1.it_value.tv_usec - e2.it_value.tv_usec) / 1000000.0);
+
+	if ((BUFCACHE_FACTOR * timing_MB) >= correction) /* more than 1MB/s */
+	printf("%2d MB in %5.2f seconds =%6.2f MB/sec\n",
+	(BUFCACHE_FACTOR * timing_MB), correction,
+	(BUFCACHE_FACTOR * timing_MB) / correction);
	else
-	printf("%3u MB in %5.2f seconds = %6.2f kB/sec\n",
-	(BUFCACHE_FACTOR * total_MB), elapsed,
-	(BUFCACHE_FACTOR * total_MB) / elapsed * 1024);
+	printf("%2d MB in %5.2f seconds =%6.2f kB/sec\n",
+	(BUFCACHE_FACTOR * timing_MB), correction,
+	(BUFCACHE_FACTOR * timing_MB) / correction * 1024);
+	correction /= BUFCACHE_FACTOR;

	flush_buffer_cache(fd);
	sleep(1);
@@ -1390,24 +1392,14 @@ quit:
	bb_perror_msg ("could not detach sharedmem buf");
	}

-	static void time_device (int fd)
+	void time_device (int fd)
	{
+	int i;
	char *buf;
	double elapsed;
	struct itimerval e1, e2;
	int shmid;
-	unsigned int max_iterations = 1024, total_MB, iterations;
-	static long parm;
-
-	//
-	// get device size
-	//
-	if (do_ctimings \|\| do_timings) {
-	if (ioctl(fd, BLKGETSIZE, &parm))
-	bb_perror_msg(" BLKGETSIZE failed");
-	else
-	max_iterations = parm / (2 * 1024) / TIMING_BUF_MB;
-	}
+	int timing_MB = TIMING_MB;

	if ((shmid = shmget(IPC_PRIVATE, TIMING_BUF_BYTES, 0600)) == -1) {
	bb_perror_msg ("could not allocate sharedmem buf");
@@ -1440,24 +1432,35 @@ static void time_device (int fd)
	setitimer(ITIMER_REAL, &(struct itimerval){{1000,0},{1000,0}}, NULL);

	/* Now do the timings for real */
-	iterations = 0;
	getitimer(ITIMER_REAL, &e1);
-	do {
-	++iterations;
-	if (read_big_block (fd, buf))
-	goto quit;
-	getitimer(ITIMER_REAL, &e2);
-	elapsed = (e1.it_value.tv_sec - e2.it_value.tv_sec)
-	+ ((e1.it_value.tv_usec - e2.it_value.tv_usec) / 1000000.0);
-	} while (elapsed < 3.0 && iterations < max_iterations);
-
-	total_MB = iterations * TIMING_BUF_MB;
-	if ((total_MB / elapsed) > 1.0) /* more than 1MB/s */
-	printf("%3u MB in %5.2f seconds = %6.2f MB/sec\n",
-	total_MB, elapsed, total_MB / elapsed);
+	for (i = TIMING_BUF_COUNT; i > 0; --i) {
+	if (read_big_block (fd, buf)) goto quit;
+	}
+	getitimer(ITIMER_REAL, &e2);
+
+	elapsed = (e1.it_value.tv_sec - e2.it_value.tv_sec)
+	+ ((e1.it_value.tv_usec - e2.it_value.tv_usec) / 1000000.0);
+	if (timing_MB >= elapsed) /* more than 1MB/s */
+	printf("%2d MB in %5.2f seconds =%6.2f MB/sec\n",
+	timing_MB, elapsed, timing_MB / elapsed);
	else
-	printf("%3u MB in %5.2f seconds = %6.2f kB/sec\n",
-	total_MB, elapsed, total_MB / elapsed * 1024);
+	printf("%2d MB in %5.2f seconds =%6.2f kB/sec\n",
+	timing_MB, elapsed, timing_MB / elapsed * 1024);
+
+	if (elapsed <= (correction * 2))
+	printf("Hmm.. suspicious results: probably not enough free memory for a proper test.\n");
+	#if 0 /* the "estimate" is just plain wrong for many systems.. */
+	else if (correction != 0.0) {
+	printf(" Estimating raw driver speed: ");
+	elapsed -= correction;
+	if (timing_MB >= elapsed) /* more than 1MB/s */
+	printf("%2d MB in %5.2f seconds =%6.2f MB/sec\n",
+	timing_MB, elapsed, timing_MB / elapsed);
+	else
+	printf("%2d MB in %5.2f seconds =%6.2f kB/sec\n",
+	timing_MB, elapsed, timing_MB / elapsed * 1024);
+	}
+	#endif
	quit:
	if (-1 == shmdt(buf))
	bb_perror_msg ("could not detach sharedmem buf");