1 /*
2 * Small tool to check for dedupable blocks in a file or device. Basically
3 * just scans the filename for extents of the given size, checksums them,
4 * and orders them up.
5 */
6 #include <stdio.h>
7 #include <stdio.h>
8 #include <unistd.h>
9 #include <inttypes.h>
10 #include <assert.h>
11 #include <sys/types.h>
12 #include <sys/stat.h>
13 #include <sys/ioctl.h>
14 #include <fcntl.h>
15 #include <string.h>
16
17 #include "../flist.h"
18 #include "../log.h"
19 #include "../mutex.h"
20 #include "../smalloc.h"
21 #include "../minmax.h"
22 #include "../crc/md5.h"
23 #include "../lib/memalign.h"
24 #include "../os/os.h"
25 #include "../gettime.h"
26 #include "../fio_time.h"
27 #include "../lib/rbtree.h"
28
29 #include "../lib/bloom.h"
30 #include "debug.h"
31
32 struct worker_thread {
33 pthread_t thread;
34
35 volatile int done;
36
37 int fd;
38 uint64_t cur_offset;
39 uint64_t size;
40
41 unsigned long items;
42 unsigned long dupes;
43 int err;
44 };
45
46 struct extent {
47 struct flist_head list;
48 uint64_t offset;
49 };
50
51 struct chunk {
52 struct rb_node rb_node;
53 uint64_t count;
54 uint32_t hash[MD5_HASH_WORDS];
55 struct flist_head extent_list[0];
56 };
57
58 struct item {
59 uint64_t offset;
60 uint32_t hash[MD5_HASH_WORDS];
61 };
62
63 static struct rb_root rb_root;
64 static struct bloom *bloom;
65 static struct fio_mutex *rb_lock;
66
67 static unsigned int blocksize = 4096;
68 static unsigned int num_threads;
69 static unsigned int chunk_size = 1048576;
70 static unsigned int dump_output;
71 static unsigned int odirect;
72 static unsigned int collision_check;
73 static unsigned int print_progress = 1;
74 static unsigned int use_bloom = 1;
75
76 static uint64_t total_size;
77 static uint64_t cur_offset;
78 static struct fio_mutex *size_lock;
79
80 static struct fio_file file;
81
get_size(struct fio_file * f,struct stat * sb)82 static uint64_t get_size(struct fio_file *f, struct stat *sb)
83 {
84 uint64_t ret;
85
86 if (S_ISBLK(sb->st_mode)) {
87 unsigned long long bytes = 0;
88
89 if (blockdev_size(f, &bytes)) {
90 log_err("dedupe: failed getting bdev size\n");
91 return 0;
92 }
93 ret = bytes;
94 } else
95 ret = sb->st_size;
96
97 return (ret & ~((uint64_t)blocksize - 1));
98 }
99
get_work(uint64_t * offset,uint64_t * size)100 static int get_work(uint64_t *offset, uint64_t *size)
101 {
102 uint64_t this_chunk;
103 int ret = 1;
104
105 fio_mutex_down(size_lock);
106
107 if (cur_offset < total_size) {
108 *offset = cur_offset;
109 this_chunk = min((uint64_t)chunk_size, total_size - cur_offset);
110 *size = this_chunk;
111 cur_offset += this_chunk;
112 ret = 0;
113 }
114
115 fio_mutex_up(size_lock);
116 return ret;
117 }
118
__read_block(int fd,void * buf,off_t offset,size_t count)119 static int __read_block(int fd, void *buf, off_t offset, size_t count)
120 {
121 ssize_t ret;
122
123 ret = pread(fd, buf, count, offset);
124 if (ret < 0) {
125 perror("pread");
126 return 1;
127 } else if (!ret)
128 return 1;
129 else if (ret != count) {
130 log_err("dedupe: short read on block\n");
131 return 1;
132 }
133
134 return 0;
135 }
136
read_block(int fd,void * buf,off_t offset)137 static int read_block(int fd, void *buf, off_t offset)
138 {
139 return __read_block(fd, buf, offset, blocksize);
140 }
141
add_item(struct chunk * c,struct item * i)142 static void add_item(struct chunk *c, struct item *i)
143 {
144 /*
145 * Save some memory and don't add extent items, if we don't
146 * use them.
147 */
148 if (dump_output || collision_check) {
149 struct extent *e;
150
151 e = malloc(sizeof(*e));
152 e->offset = i->offset;
153 flist_add_tail(&e->list, &c->extent_list[0]);
154 }
155
156 c->count++;
157 }
158
col_check(struct chunk * c,struct item * i)159 static int col_check(struct chunk *c, struct item *i)
160 {
161 struct extent *e;
162 char *cbuf, *ibuf;
163 int ret = 1;
164
165 cbuf = fio_memalign(blocksize, blocksize);
166 ibuf = fio_memalign(blocksize, blocksize);
167
168 e = flist_entry(c->extent_list[0].next, struct extent, list);
169 if (read_block(file.fd, cbuf, e->offset))
170 goto out;
171
172 if (read_block(file.fd, ibuf, i->offset))
173 goto out;
174
175 ret = memcmp(ibuf, cbuf, blocksize);
176 out:
177 fio_memfree(cbuf, blocksize);
178 fio_memfree(ibuf, blocksize);
179 return ret;
180 }
181
alloc_chunk(void)182 static struct chunk *alloc_chunk(void)
183 {
184 struct chunk *c;
185
186 if (collision_check || dump_output) {
187 c = malloc(sizeof(struct chunk) + sizeof(struct flist_head));
188 INIT_FLIST_HEAD(&c->extent_list[0]);
189 } else
190 c = malloc(sizeof(struct chunk));
191
192 return c;
193 }
194
insert_chunk(struct item * i)195 static void insert_chunk(struct item *i)
196 {
197 struct rb_node **p, *parent;
198 struct chunk *c;
199 int diff;
200
201 p = &rb_root.rb_node;
202 parent = NULL;
203 while (*p) {
204 parent = *p;
205
206 c = rb_entry(parent, struct chunk, rb_node);
207 diff = memcmp(i->hash, c->hash, sizeof(i->hash));
208 if (diff < 0)
209 p = &(*p)->rb_left;
210 else if (diff > 0)
211 p = &(*p)->rb_right;
212 else {
213 int ret;
214
215 if (!collision_check)
216 goto add;
217
218 fio_mutex_up(rb_lock);
219 ret = col_check(c, i);
220 fio_mutex_down(rb_lock);
221
222 if (!ret)
223 goto add;
224
225 p = &(*p)->rb_right;
226 }
227 }
228
229 c = alloc_chunk();
230 RB_CLEAR_NODE(&c->rb_node);
231 c->count = 0;
232 memcpy(c->hash, i->hash, sizeof(i->hash));
233 rb_link_node(&c->rb_node, parent, p);
234 rb_insert_color(&c->rb_node, &rb_root);
235 add:
236 add_item(c, i);
237 }
238
insert_chunks(struct item * items,unsigned int nitems,uint64_t * ndupes)239 static void insert_chunks(struct item *items, unsigned int nitems,
240 uint64_t *ndupes)
241 {
242 int i;
243
244 fio_mutex_down(rb_lock);
245
246 for (i = 0; i < nitems; i++) {
247 if (bloom) {
248 unsigned int s;
249 int r;
250
251 s = sizeof(items[i].hash) / sizeof(uint32_t);
252 r = bloom_set(bloom, items[i].hash, s);
253 *ndupes += r;
254 } else
255 insert_chunk(&items[i]);
256 }
257
258 fio_mutex_up(rb_lock);
259 }
260
crc_buf(void * buf,uint32_t * hash)261 static void crc_buf(void *buf, uint32_t *hash)
262 {
263 struct fio_md5_ctx ctx = { .hash = hash };
264
265 fio_md5_init(&ctx);
266 fio_md5_update(&ctx, buf, blocksize);
267 fio_md5_final(&ctx);
268 }
269
read_blocks(int fd,void * buf,off_t offset,size_t size)270 static unsigned int read_blocks(int fd, void *buf, off_t offset, size_t size)
271 {
272 if (__read_block(fd, buf, offset, size))
273 return 0;
274
275 return size / blocksize;
276 }
277
do_work(struct worker_thread * thread,void * buf)278 static int do_work(struct worker_thread *thread, void *buf)
279 {
280 unsigned int nblocks, i;
281 off_t offset;
282 int nitems = 0;
283 uint64_t ndupes = 0;
284 struct item *items;
285
286 offset = thread->cur_offset;
287
288 nblocks = read_blocks(thread->fd, buf, offset, min(thread->size, (uint64_t)chunk_size));
289 if (!nblocks)
290 return 1;
291
292 items = malloc(sizeof(*items) * nblocks);
293
294 for (i = 0; i < nblocks; i++) {
295 void *thisptr = buf + (i * blocksize);
296
297 items[i].offset = offset;
298 crc_buf(thisptr, items[i].hash);
299 offset += blocksize;
300 nitems++;
301 }
302
303 insert_chunks(items, nitems, &ndupes);
304
305 free(items);
306 thread->items += nitems;
307 thread->dupes += ndupes;
308 return 0;
309 }
310
thread_fn(void * data)311 static void *thread_fn(void *data)
312 {
313 struct worker_thread *thread = data;
314 void *buf;
315
316 buf = fio_memalign(blocksize, chunk_size);
317
318 do {
319 if (get_work(&thread->cur_offset, &thread->size)) {
320 thread->err = 1;
321 break;
322 }
323 if (do_work(thread, buf)) {
324 thread->err = 1;
325 break;
326 }
327 } while (1);
328
329 thread->done = 1;
330 fio_memfree(buf, chunk_size);
331 return NULL;
332 }
333
show_progress(struct worker_thread * threads,unsigned long total)334 static void show_progress(struct worker_thread *threads, unsigned long total)
335 {
336 unsigned long last_nitems = 0;
337 struct timeval last_tv;
338
339 fio_gettime(&last_tv, NULL);
340
341 while (print_progress) {
342 unsigned long this_items;
343 unsigned long nitems = 0;
344 uint64_t tdiff;
345 float perc;
346 int some_done = 0;
347 int i;
348
349 for (i = 0; i < num_threads; i++) {
350 nitems += threads[i].items;
351 some_done = threads[i].done;
352 if (some_done)
353 break;
354 }
355
356 if (some_done)
357 break;
358
359 perc = (float) nitems / (float) total;
360 perc *= 100.0;
361 this_items = nitems - last_nitems;
362 this_items *= blocksize;
363 tdiff = mtime_since_now(&last_tv);
364 if (tdiff) {
365 this_items = (this_items * 1000) / (tdiff * 1024);
366 printf("%3.2f%% done (%luKiB/sec)\r", perc, this_items);
367 last_nitems = nitems;
368 fio_gettime(&last_tv, NULL);
369 } else
370 printf("%3.2f%% done\r", perc);
371 fflush(stdout);
372 usleep(250000);
373 };
374 }
375
run_dedupe_threads(struct fio_file * f,uint64_t dev_size,uint64_t * nextents,uint64_t * nchunks)376 static int run_dedupe_threads(struct fio_file *f, uint64_t dev_size,
377 uint64_t *nextents, uint64_t *nchunks)
378 {
379 struct worker_thread *threads;
380 unsigned long nitems, total_items;
381 int i, err = 0;
382
383 total_size = dev_size;
384 total_items = dev_size / blocksize;
385 cur_offset = 0;
386 size_lock = fio_mutex_init(FIO_MUTEX_UNLOCKED);
387
388 threads = malloc(num_threads * sizeof(struct worker_thread));
389 for (i = 0; i < num_threads; i++) {
390 memset(&threads[i], 0, sizeof(struct worker_thread));
391 threads[i].fd = f->fd;
392
393 err = pthread_create(&threads[i].thread, NULL, thread_fn, &threads[i]);
394 if (err) {
395 log_err("fio: thread startup failed\n");
396 break;
397 }
398 }
399
400 show_progress(threads, total_items);
401
402 nitems = 0;
403 *nextents = 0;
404 *nchunks = 1;
405 for (i = 0; i < num_threads; i++) {
406 void *ret;
407 pthread_join(threads[i].thread, &ret);
408 nitems += threads[i].items;
409 *nchunks += threads[i].dupes;
410 }
411
412 printf("Threads(%u): %lu items processed\n", num_threads, nitems);
413
414 *nextents = nitems;
415 *nchunks = nitems - *nchunks;
416
417 fio_mutex_remove(size_lock);
418 free(threads);
419 return err;
420 }
421
dedupe_check(const char * filename,uint64_t * nextents,uint64_t * nchunks)422 static int dedupe_check(const char *filename, uint64_t *nextents,
423 uint64_t *nchunks)
424 {
425 uint64_t dev_size;
426 struct stat sb;
427 int flags;
428
429 flags = O_RDONLY;
430 if (odirect)
431 flags |= OS_O_DIRECT;
432
433 memset(&file, 0, sizeof(file));
434 file.file_name = strdup(filename);
435
436 file.fd = open(filename, flags);
437 if (file.fd == -1) {
438 perror("open");
439 goto err;
440 }
441
442 if (fstat(file.fd, &sb) < 0) {
443 perror("fstat");
444 goto err;
445 }
446
447 dev_size = get_size(&file, &sb);
448 if (!dev_size)
449 goto err;
450
451 if (use_bloom) {
452 uint64_t bloom_entries;
453
454 bloom_entries = 8 * (dev_size / blocksize);
455 bloom = bloom_new(bloom_entries);
456 }
457
458 printf("Will check <%s>, size <%llu>, using %u threads\n", filename, (unsigned long long) dev_size, num_threads);
459
460 return run_dedupe_threads(&file, dev_size, nextents, nchunks);
461 err:
462 if (file.fd != -1)
463 close(file.fd);
464 free(file.file_name);
465 return 1;
466 }
467
show_chunk(struct chunk * c)468 static void show_chunk(struct chunk *c)
469 {
470 struct flist_head *n;
471 struct extent *e;
472
473 printf("c hash %8x %8x %8x %8x, count %lu\n", c->hash[0], c->hash[1], c->hash[2], c->hash[3], (unsigned long) c->count);
474 flist_for_each(n, &c->extent_list[0]) {
475 e = flist_entry(n, struct extent, list);
476 printf("\toffset %llu\n", (unsigned long long) e->offset);
477 }
478 }
479
show_stat(uint64_t nextents,uint64_t nchunks)480 static void show_stat(uint64_t nextents, uint64_t nchunks)
481 {
482 double perc, ratio;
483
484 printf("Extents=%lu, Unique extents=%lu\n", (unsigned long) nextents, (unsigned long) nchunks);
485
486 if (nchunks) {
487 ratio = (double) nextents / (double) nchunks;
488 printf("De-dupe ratio: 1:%3.2f\n", ratio - 1.0);
489 } else
490 printf("De-dupe ratio: 1:infinite\n");
491
492 perc = 1.00 - ((double) nchunks / (double) nextents);
493 perc *= 100.0;
494 printf("Fio setting: dedupe_percentage=%u\n", (int) (perc + 0.50));
495
496 }
497
iter_rb_tree(uint64_t * nextents,uint64_t * nchunks)498 static void iter_rb_tree(uint64_t *nextents, uint64_t *nchunks)
499 {
500 struct rb_node *n;
501
502 *nchunks = *nextents = 0;
503
504 n = rb_first(&rb_root);
505 if (!n)
506 return;
507
508 do {
509 struct chunk *c;
510
511 c = rb_entry(n, struct chunk, rb_node);
512 (*nchunks)++;
513 *nextents += c->count;
514
515 if (dump_output)
516 show_chunk(c);
517
518 } while ((n = rb_next(n)) != NULL);
519 }
520
usage(char * argv[])521 static int usage(char *argv[])
522 {
523 log_err("Check for dedupable blocks on a device/file\n\n");
524 log_err("%s: [options] <device or file>\n", argv[0]);
525 log_err("\t-b\tChunk size to use\n");
526 log_err("\t-t\tNumber of threads to use\n");
527 log_err("\t-d\tFull extent/chunk debug output\n");
528 log_err("\t-o\tUse O_DIRECT\n");
529 log_err("\t-c\tFull collision check\n");
530 log_err("\t-B\tUse probabilistic bloom filter\n");
531 log_err("\t-p\tPrint progress indicator\n");
532 return 1;
533 }
534
main(int argc,char * argv[])535 int main(int argc, char *argv[])
536 {
537 uint64_t nextents = 0, nchunks = 0;
538 int c, ret;
539
540 arch_init(argv);
541 debug_init();
542
543 while ((c = getopt(argc, argv, "b:t:d:o:c:p:B:")) != -1) {
544 switch (c) {
545 case 'b':
546 blocksize = atoi(optarg);
547 break;
548 case 't':
549 num_threads = atoi(optarg);
550 break;
551 case 'd':
552 dump_output = atoi(optarg);
553 break;
554 case 'o':
555 odirect = atoi(optarg);
556 break;
557 case 'c':
558 collision_check = atoi(optarg);
559 break;
560 case 'p':
561 print_progress = atoi(optarg);
562 break;
563 case 'B':
564 use_bloom = atoi(optarg);
565 break;
566 case '?':
567 default:
568 return usage(argv);
569 }
570 }
571
572 if (collision_check || dump_output)
573 use_bloom = 0;
574
575 if (!num_threads)
576 num_threads = cpus_online();
577
578 if (argc == optind)
579 return usage(argv);
580
581 sinit();
582
583 rb_root = RB_ROOT;
584 rb_lock = fio_mutex_init(FIO_MUTEX_UNLOCKED);
585
586 ret = dedupe_check(argv[optind], &nextents, &nchunks);
587
588 if (!ret) {
589 if (!bloom)
590 iter_rb_tree(&nextents, &nchunks);
591
592 show_stat(nextents, nchunks);
593 }
594
595 fio_mutex_remove(rb_lock);
596 if (bloom)
597 bloom_free(bloom);
598 scleanup();
599 return ret;
600 }
601