├── LICENSE ├── README.md └── subvolume.py /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. By contrast, 15 | the GNU General Public License is intended to guarantee your freedom to 16 | share and change all versions of a program--to make sure it remains free 17 | software for all its users. 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It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # btrfs-snapshot-diff 2 | Find the differences between btrfs snapshots, no quota activation in btrfs needed! 3 | 4 | Btrfs, as a CoW filesystem, has a problem identifying the size of a snapshot and the differences between snapshots. 5 | By using [python-btrfs](https://github.com/knorrie/python-btrfs), it is possible to parse the metadata of a btrfs filesystem and find the differences between subvolumes/snapshots. 6 | 7 | ## Currently implemented functionality: 8 | 9 | This tool can approximately identify how much space will be freed when a snapshot is deleted. 10 | 11 | ## How it works: 12 | 13 | This tool identifies all subvolumes of a btrfs filesystem. For each subvolume all file extents which are not inline are parsed and kept. All other items are ignored. 14 | 15 | Thus, we create a tree of extents & ranges together with the snapshots that use them: 16 | 17 | 1. file extent 1 18 | 1. range1: [Snapshot 1, Snapshot 2] 19 | 2. range2: [Snapshot 3] 20 | 3. ... 21 | 2. file extent 2 22 | 1. range1: [...] 23 | 2. range2: [...] 24 | 25 | Now, the actual disk size of Snapshot 1 can be extracted from each file extent 26 | ## Usage: 27 | 28 | [python-btrfs](https://github.com/knorrie/python-btrfs) must be installed. 29 | 30 | Program is single threaded, it could use a lot of memory and it puts a lot of read stress in disks. It could take many minutes. ionice it & monitor its memory usage. Memory usage & execution time depend on the dataset. The program does not perform any write operations. Do not modify subvolume/snapshot during execution. Try not to write any data to any subvolume or execute dedup programs in parallel. 31 | 32 | `subvolume.py [-u] [-f] [-r ] /path/to/btrfs/ [ -i | -o ] [ ]` 33 | 34 | `-u` calculates the unique data occupied by each snapshot. Thus, `-r` makes no sense. Specifying subvolumes to ignore can mess with `-u` results because the specified subvolume data will not be parsed! 35 | `-f` finds the files that might contribute to the unique extents. 36 | `-i` makes the program to ignore the specified subvolumes, which is also the default behaviour if no `-i` or `-o` argument is specified but subvolumes are given. 37 | `-o` makes the program to analyze only the specified subvolumes. 38 | 39 | You can find subvolume ids by using: 40 | `btrfs subvolume list /path/to/btrfs` 41 | 42 | ## Example: 43 | 44 | `btrfs subvolume list /path/to/btrfs`: 45 | 46 | ``` 47 | ID 258 gen 15649 top level 5 path mydata 48 | ID 259 gen 15651 top level 5 path subvol_snapshots 49 | ID 1949 gen 3785 top level 259 path subvol_snapshots/283/snapshot 50 | ID 2133 gen 5080 top level 259 path subvol_snapshots/435/snapshot 51 | ID 2395 gen 6616 top level 259 path subvol_snapshots/660/snapshot 52 | ID 2694 gen 8781 top level 259 path subvol_snapshots/888/snapshot 53 | ID 3661 gen 10830 top level 259 path subvol_snapshots/1126/snapshot 54 | ID 3818 gen 11948 top level 259 path subvol_snapshots/1228/snapshot 55 | ID 3887 gen 12351 top level 259 path subvol_snapshots/1285/snapshot 56 | ID 3942 gen 12628 top level 259 path subvol_snapshots/1333/snapshot 57 | ID 4040 gen 13778 top level 259 path subvol_snapshots/1412/snapshot 58 | ID 4072 gen 13778 top level 259 path subvol_snapshots/1438/snapshot 59 | ID 4091 gen 13778 top level 259 path subvol_snapshots/1452/snapshot 60 | ID 4130 gen 13853 top level 259 path subvol_snapshots/1477/snapshot 61 | ID 4166 gen 14537 top level 259 path subvol_snapshots/1509/snapshot 62 | ID 4182 gen 14537 top level 259 path subvol_snapshots/1523/snapshot 63 | ID 4196 gen 14537 top level 259 path subvol_snapshots/1535/snapshot 64 | ID 4211 gen 14753 top level 259 path subvol_snapshots/1545/snapshot 65 | ID 4258 gen 15274 top level 259 path subvol_snapshots/1582/snapshot 66 | ID 4337 gen 15274 top level 259 path subvol_snapshots/1652/snapshot 67 | ID 4372 gen 15274 top level 259 path subvol_snapshots/1680/snapshot 68 | ID 4392 gen 15341 top level 259 path subvol_snapshots/1691/snapshot 69 | ID 4414 gen 15434 top level 259 path subvol_snapshots/1712/snapshot 70 | ID 4444 gen 15538 top level 259 path subvol_snapshots/1740/snapshot 71 | ID 4451 gen 15566 top level 259 path subvol_snapshots/1747/snapshot 72 | ID 4452 gen 15570 top level 259 path subvol_snapshots/1748/snapshot 73 | ID 4454 gen 15581 top level 259 path subvol_snapshots/1749/snapshot 74 | ID 4455 gen 15584 top level 259 path subvol_snapshots/1750/snapshot 75 | ID 4456 gen 15589 top level 259 path subvol_snapshots/1751/snapshot 76 | ID 4457 gen 15592 top level 259 path subvol_snapshots/1752/snapshot 77 | ID 4458 gen 15596 top level 259 path subvol_snapshots/1753/snapshot 78 | ID 4459 gen 15598 top level 259 path subvol_snapshots/1754/snapshot 79 | ID 4460 gen 15611 top level 259 path subvol_snapshots/1755/snapshot 80 | ID 4461 gen 15612 top level 259 path subvol_snapshots/1756/snapshot 81 | ID 4462 gen 15620 top level 259 path subvol_snapshots/1757/snapshot 82 | ID 4463 gen 15639 top level 259 path subvol_snapshots/1758/snapshot 83 | ID 4464 gen 15643 top level 259 path subvol_snapshots/1759/snapshot 84 | ID 4465 gen 15646 top level 259 path subvol_snapshots/1760/snapshot 85 | ID 4466 gen 15649 top level 259 path subvol_snapshots/1761/snapshot 86 | ``` 87 | 88 | `subvolume.py -r 258 /path/to/btrfs/ 259`: 89 | 90 | ``` 91 | Unique File Extents Extents added ontop Extents added ontop of 92 | per subvolume of previous subvolume current(act) subvolume 93 | ---------------------|---------------------|---------------------- 94 | SubvolumId Size Size Size 95 | 258 0.00B 0.00B 1.46TiB 96 | 4466 0.00B 0.00B 0.00B 97 | 4465 0.00B 0.00B 0.00B 98 | 4464 0.00B 0.00B 0.00B 99 | 4463 0.00B 2.58MiB 0.00B 100 | 4462 0.00B 0.00B 648.00KiB 101 | 4461 0.00B 0.00B 648.00KiB 102 | 4460 0.00B 1.18MiB 648.00KiB 103 | 4459 0.00B 0.00B 996.00KiB 104 | 4458 0.00B 0.00B 996.00KiB 105 | 4457 0.00B 0.00B 996.00KiB 106 | 4456 0.00B 0.00B 996.00KiB 107 | 4455 0.00B 0.00B 996.00KiB 108 | 4454 0.00B 0.00B 996.00KiB 109 | 4452 0.00B 0.00B 996.00KiB 110 | 4451 0.00B 0.00B 996.00KiB 111 | 4444 0.00B 1.23MiB 996.00KiB 112 | 4414 120.00KiB 12.38MiB 1.07MiB 113 | 4392 184.00KiB 6.20GiB 1.19MiB 114 | 4372 164.00KiB 3.64MiB 4.41MiB 115 | 4337 176.00KiB 6.47MiB 4.48MiB 116 | 4258 0.00B 1010.53MiB 4.91MiB 117 | 4211 0.00B 1.97GiB 4.91MiB 118 | 4196 36.00KiB 36.00KiB 5.64MiB 119 | 4182 36.00KiB 3.66MiB 5.64MiB 120 | 4166 140.00KiB 590.95MiB 5.80MiB 121 | 4130 192.00KiB 6.04GiB 5.83MiB 122 | 4091 1.75MiB 34.36MiB 7.49MiB 123 | 4072 296.00KiB 9.12MiB 8.09MiB 124 | 4040 8.96MiB 11.01GiB 16.72MiB 125 | 3942 2.31MiB 4.16GiB 8.67MiB 126 | 3887 1.59MiB 4.15GiB 27.33MiB 127 | 3818 1.22MiB 15.20GiB 27.41MiB 128 | 3661 2.43MiB 13.61GiB 27.43MiB 129 | 2694 3.19MiB 40.44GiB 27.42MiB 130 | 2395 6.55MiB 13.25GiB 62.80MiB 131 | 2133 5.99MiB 17.44GiB 119.27MiB 132 | 1949 42.48MiB 1.33TiB 166.50MiB 133 | Size/Cost of snapshots: 77.78MiB Volatility: 0.01% 134 | ``` 135 | Snapshot 2133 introduced 17GiB, where most of them still reside on the system (used by newer snapshot, 2395) 136 | Thus, deleting snapshot 2133, will only free 6MiB. Snapshot 2133 has 119MiB changed compared to current/ active (258) subvolume. 137 | When using `-u` argument only the first column has values. 138 | 139 | Files result example: 140 | ``` 141 | Possible Unique Files: 142 | beeshash.dat/ : {4652} 143 | beescrawl.dat/ : {4652} 144 | beesstats.txt/ : {4652} 145 | 2708/filelist-2700.txt/ : {259} 146 | 2744/filelist-2741.txt/ : {259} 147 | 2752/filelist-2744.txt/ : {259} 148 | 2795/filelist-2789.txt/ : {259} 149 | ``` 150 | 151 | 152 | ## Possible expansions: 153 | 154 | Calculate the size of metadata block differences. 155 | Take into consideration inline file extents. 156 | Why do we recieve the same extent with the same range many times? 157 | -------------------------------------------------------------------------------- /subvolume.py: -------------------------------------------------------------------------------- 1 | #!/usr/bin/python3 2 | 3 | # Copyright (C) 2018 Dimitris Georgiou 4 | 5 | # This program is free software: you can redistribute it and/or modify 6 | # it under the terms of the GNU General Public License as published by 7 | # the Free Software Foundation, either version 3 of the License, or 8 | # (at your option) any later version. 9 | 10 | # This program is distributed in the hope that it will be useful, 11 | # but WITHOUT ANY WARRANTY; without even the implied warranty of 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 | # GNU General Public License for more details. 14 | 15 | # You should have received a copy of the GNU General Public License 16 | # along with this program. If not, see . 17 | 18 | import btrfs 19 | import argparse 20 | import sys 21 | from collections import deque 22 | from collections import Counter 23 | from collections import defaultdict 24 | import math, array 25 | from functools import lru_cache 26 | import multiprocessing,os 27 | import bisect 28 | 29 | #function to convert a pair of positive integers to a single integer 30 | #we want to decrease memory consumption, thus we need this trick 31 | #http://szudzik.com/ElegantPairing.pdf 32 | #cache the results for speed up 33 | 34 | @lru_cache(maxsize=1024) 35 | def unique_number(x,y): 36 | result=x 37 | if x >=y: 38 | result+=y 39 | result+=x**2 40 | else: 41 | result+=y**2 42 | return result 43 | 44 | #undo the above function, return x,y based on a single number 45 | #also cache the results 46 | 47 | @lru_cache(maxsize=1024) 48 | def unique_to_pair(number): 49 | root=int(math.floor(math.sqrt(number))) 50 | crit=number-root**2 51 | if crit< root: 52 | x=crit 53 | y=root 54 | else: 55 | x=root 56 | y=crit-root 57 | return x,y 58 | 59 | #take a list of 'paired' numbers and return the x coordinate, which is snapshot 60 | #stored into the pair 61 | def return_snapshots(mylist): 62 | result=[] 63 | for item in mylist: 64 | snapshot,_=unique_to_pair(item) 65 | result.append(snapshot) 66 | return result 67 | 68 | #take a list of 'paired' numbers and return the paired number that has the same 69 | #x coordinate, which is the snapshot stored into the pair. if shallow search only 70 | #the last element 71 | def return_coded(mylist,snapshot,shallow): 72 | if shallow: 73 | snapshot_pair,_=unique_to_pair(mylist[-1]) 74 | if snapshot_pair == snapshot: 75 | return mylist[-1] 76 | return None 77 | for item in mylist: 78 | snapshot_pair,_=unique_to_pair(item) 79 | if snapshot_pair == snapshot: 80 | return item 81 | return None 82 | 83 | 84 | #take a paired number and compare it with a snapshot 85 | #cache the results for speedup 86 | @lru_cache(maxsize=1024) 87 | def compare_pair_to_snapshot(item,snapshot): 88 | snapshot_pair,_=unique_to_pair(item) 89 | if snapshot_pair == snapshot: 90 | return True 91 | return False 92 | 93 | #find an item that has the same subvolume and remove it 94 | def remove_snapshot_from_list(mylist,snapshot,shallow): 95 | coded =return_coded(mylist,snapshot,shallow) 96 | if coded != None: 97 | mylist.remove(coded) 98 | return mylist 99 | 100 | #find if an item with the same snapshot exists in the list 101 | def find_snapshot_in_list(mylist,snapshot,shallow): 102 | if shallow: 103 | if compare_pair_to_snapshot(mylist[-1],snapshot): 104 | return True 105 | else: 106 | return False 107 | for item in mylist: 108 | if compare_pair_to_snapshot(item,snapshot): 109 | return True 110 | return False 111 | 112 | #function to calculate subtraction between 2 integer intervals 113 | def range_sub(range1,range2): 114 | result=[] 115 | a,b=range1 116 | x,y=range2 117 | if x>b or y=b: 121 | if x>a: 122 | b=x-1 123 | else: 124 | return result 125 | else: 126 | if x>a: 127 | result.append((a,x-1)) 128 | a=y+1 129 | result.append((a,b)) 130 | return result 131 | 132 | 133 | #Class to implement intervals, we only care about subtraction 134 | class Ranges: 135 | def __init__(self,start=None,stop=None): 136 | self.list=[] 137 | self.upper=None 138 | self.lower=None 139 | if start!=None: 140 | self.list.append((start,stop)) 141 | self.upper=stop 142 | self.lower=start 143 | 144 | def is_empty(self): 145 | if len(self.list)>=1: 146 | return False 147 | return True 148 | 149 | def __sub__(self,other): 150 | final_result=Ranges() 151 | queue=deque(self.list) 152 | 153 | while queue: 154 | item = queue.popleft() 155 | #this could be optiomized more 156 | for otheritem in other.list: 157 | result=range_sub(item,otheritem) 158 | if len(result)>1: 159 | queue.appendleft(result[1]) 160 | item=result[0] 161 | elif len(result)==1: 162 | item=result[0] 163 | else: 164 | item=None 165 | break 166 | #print item 167 | if item !=None: 168 | final_result.append(item) 169 | return final_result 170 | 171 | def append(self,myrange): 172 | self.list.append(myrange) 173 | self.upper=myrange[1] 174 | if self.lower==None: 175 | self.lower=myrange[0] 176 | 177 | def __str__(self): 178 | return(str(self.list)) 179 | 180 | #Class to hold data. It's a dictionary of dictionaries. 181 | #tree[key of the extent]= {range1: [list of paired (snapshot,inode)],range2: [list of paired (snapshot,inode)]} 182 | #inodes data are used to find which files hold data of unique extents. 183 | class TreeWrapper: 184 | def __init__(self): 185 | self._tree=dict() 186 | self._snapshots=[] 187 | #self._inodes=dict() 188 | 189 | 190 | #check if the current tree has data for this extent/key. 191 | #if it has, check if the current extent range is already parsed. 192 | def delete_range(self,key,limit,tree,shallow): 193 | snapshotinodelist=self._tree[key][limit] 194 | #print(snapshotinodelist) 195 | remove_snapshot_from_list(snapshotinodelist,tree,shallow) 196 | #print(self._tree[key][limit]) 197 | if len(self._tree[key][limit])==0: 198 | del self._tree[key][limit] 199 | 200 | #use array instead of list because integers consume too much memory in python 201 | def add_range(self,key,limit,mypair): 202 | if key in self._tree.keys(): 203 | if limit in self._tree[key].keys(): 204 | self._tree[key][limit].append(mypair) 205 | else: 206 | self._tree[key][limit]=array.array('Q') 207 | self._tree[key][limit].append(mypair) 208 | else: 209 | self._tree[key]=dict() 210 | self._tree[key][limit]=array.array('Q') 211 | self._tree[key][limit].append(mypair) 212 | 213 | #unfortunately some extents reappear, maybe there are dedup or reflink? 214 | #so we need to take care of that by calculating exactly the data that each 215 | #subvolume uses 216 | def add(self,tree,key,start,stop,inode): 217 | mypair=unique_number(tree,inode) 218 | if key in self._tree.keys(): 219 | extent=self._tree[key] 220 | #find all ranges that have data for this subvolume in this extent 221 | #do not search deep, since we add one subvolume at a time 222 | ranges=[] 223 | for myrange,snapshotinodelist in extent.items(): 224 | if find_snapshot_in_list(snapshotinodelist,tree,False): 225 | ranges.append(myrange) 226 | ranges.sort() 227 | 228 | #start of intervals for this key and tree are in even positions 229 | #ends are in odd positions 230 | starts=ranges[::2] 231 | stops=ranges[1::2] 232 | if len(starts)!=len(stops): 233 | print("problem",key,ranges) 234 | sys.exit(0) 235 | 236 | #if the data we are trying to push already exist, ignore them 237 | if start in starts: 238 | index=starts.index(start) 239 | if stop == stops[index]: 240 | #print(ranges,start,stop) 241 | return 242 | 243 | #Algorithm: we have these intervals: 0...100, 150...200 244 | #and we want to add 80...170 245 | #the final result must be 0...200 because this extent is used 246 | #interely by this snapshot 247 | 248 | #For each base, calculate base - target. If the base 249 | #interval is modified then delete that end because new data will 250 | #be added. Then target becomes target-base and continue with the next base 251 | 252 | #try to minimize the subtractions needed 253 | realstart=bisect.bisect_left(starts,start) 254 | realstop=bisect.bisect_right(stops,stop) 255 | if realstart > 0: 256 | #print(realstart,starts,start) 257 | realstart-=1 258 | mystarts=starts[realstart:realstop+1] 259 | mystops=stops[realstart:realstop+1] 260 | if len(mystarts)>0: 261 | if mystops[-1]0: 265 | if mystarts[0]>stop: 266 | mystarts=mystarts[1:] 267 | 268 | #target is the interval we are trying to add 269 | target=Ranges(start,stop) 270 | for i, oldstart in enumerate(mystarts): 271 | #base is the interval that we must analyze 272 | base=Ranges(oldstart,mystops[i]) 273 | newbase=base-target 274 | #if newbase differs in an end of base then that end must 275 | #be deleted because the end of the interval will be added 276 | if base.lower>target.lower and newbase.lower!=base.lower: 277 | self.delete_range(key,base.lower,tree,False) 278 | if base.upper=1: 345 | try: 346 | size=iterableview[i+1][0]-myrange 347 | result+=size 348 | except: 349 | print(extent,sorted(rangedict.items()),mytuple) 350 | return result 351 | 352 | #find those ranges that have only one snapshot, if this snapshot is deleted 353 | #this space will be freed. 354 | #based on the scenario of transform is should return: 355 | #result[tree1]=pos2-pos1+pos4-pos3 356 | #result[tree2]=0 357 | #if files are analyzed use the inode data to find them ans store them in different dictionary. 358 | def find_unique(self,fs,analyze_file): 359 | result=Counter() 360 | result_data=defaultdict(set) 361 | for extent,rangedict in self._tree.items(): 362 | iterableview = sorted(rangedict.items()) 363 | for i,mytuple in enumerate(iterableview): 364 | myrange,unique_pair_list=mytuple 365 | #myset=list(myset) 366 | if len(unique_pair_list)==1: 367 | subvolume,inode=unique_to_pair(unique_pair_list[0]) 368 | size=iterableview[i+1][0]-myrange 369 | result[subvolume]+=size 370 | #result[myset[0]]+=size 371 | #print(inode) 372 | if analyze_file: 373 | try: 374 | file=btrfs.ioctl.ino_lookup(fs.fd,subvolume,inode) 375 | result_data[file.name_bytes.decode('utf-8')].add(subvolume) 376 | except: 377 | print("Inode not found",inode) 378 | return result,result_data 379 | 380 | #helper function to find the size of the extend ranges that have the desired snapshots 381 | def find_snapshots_size(self,wanted,not_wanted): 382 | result=0 383 | for extent,rangedict in self._tree.items(): 384 | rangelist = sorted(rangedict.keys()) 385 | for i,myrange in enumerate(rangelist): 386 | snapshots=set(return_snapshots(rangedict[myrange])) 387 | if len(set(wanted) & snapshots)>0 and len(set(not_wanted) & snapshots) ==0: 388 | try: 389 | result+=rangelist[i+1]-myrange 390 | except: 391 | print(wanted,not_wanted) 392 | print(extent,sorted(rangedict.items()),myrange) 393 | return result 394 | 395 | #the active subvolume must be the last one 396 | def add_snapshots(self,snapshots): 397 | self._snapshots=snapshots.copy() 398 | 399 | #calculate the size of ranges ontop of the previous subvolume 400 | #older subvolumes must be first in subvolume list 401 | def find_snapshot_size_to_previous(self): 402 | results=Counter() 403 | for i, snapshot in enumerate(self._snapshots): 404 | if i>0: 405 | results[snapshot]+=self.find_snapshots_size([snapshot],[self._snapshots[i-1]]) 406 | else: 407 | results[snapshot]+=self.find_snapshots_size([snapshot],[]) 408 | return results 409 | 410 | #calculate the size of ranges ontop of the current active subvolume 411 | def find_snapshot_size_to_current(self): 412 | results=Counter() 413 | current=self._snapshots[-1] 414 | for snapshot in self._snapshots: 415 | if snapshot == current: 416 | results[snapshot]+=self.find_snapshots_size([snapshot],[]) 417 | else: 418 | results[snapshot]+=self.find_snapshots_size([snapshot],[current]) 419 | return results 420 | 421 | def disk_parse_queue(semaphore,lock,barrier,queue,path,tree): 422 | with semaphore: 423 | pid = os.getpid() 424 | print("Parsing subvolume:",tree,"pid",pid) 425 | fs=btrfs.FileSystem(path) 426 | min_key=btrfs.ctree.Key(0,btrfs.ctree.EXTENT_DATA_KEY,0) 427 | for header, data in btrfs.ioctl.search_v2(fs.fd, tree,min_key): 428 | if header.type == btrfs.ctree.EXTENT_DATA_KEY: 429 | datum=btrfs.ctree.FileExtentItem(header,data) 430 | if datum.type != btrfs.ctree.FILE_EXTENT_INLINE:# and datum.disk_bytenr !=0: 431 | key=unique_number(datum.disk_bytenr,datum.disk_num_bytes) 432 | #key = pool.apply(unique_number, (datum.disk_bytenr,datum.disk_num_bytes,)) 433 | stop=datum.offset+datum.num_bytes 434 | #key=res.get() 435 | queue.put((key,datum.offset,stop,datum.key.objectid,tree)) 436 | if lock.acquire(timeout=0): 437 | #print("Waiting for queue to empty",tree,pid) 438 | queue.join() 439 | #print("queue emptied",tree,pid) 440 | lock.release() 441 | #queue.put(None) 442 | os.close(fs.fd) 443 | del fs 444 | if lock.acquire(): 445 | #print("Waiting for queue to empty",tree,pid) 446 | queue.join() 447 | #print("queue emptied",tree,pid) 448 | print("Finished subvolume:",tree,pid) 449 | lock.release() 450 | i=barrier.wait() 451 | if i == 0: 452 | queue.put(None) 453 | queue.join() 454 | queue.close() 455 | 456 | 457 | def main(): 458 | multiprocessing.set_start_method('spawn') 459 | parser = argparse.ArgumentParser() 460 | parser.add_argument("-u","--unique",action='store_true',help="calculate only unique data, -r argument makes no sense if -u is active") 461 | parser.add_argument("-f","--files",action='store_true',help="find filenames that exist in unique extents") 462 | parser.add_argument("path", type=str, 463 | help="path of the btrfs filesystem") 464 | parser.add_argument("-r", "--root", type=int,default=5, 465 | help="current active subvolume to analyze first, default is 5") 466 | parser.add_argument("-c", "--cpus", type=int, default=2*len(os.sched_getaffinity(0)), 467 | help="Number of disk reading processes to spawn. More processes means more memory usage.") 468 | group = parser.add_mutually_exclusive_group() 469 | group.add_argument('-i', '--ignore', action='store_true',help="Do not analyze the specified subvolumes") 470 | group.add_argument('-o', '--only', action='store_true',help="Analyze only the specified subvolumes") 471 | parser.add_argument('subvolume', nargs='*', type=int, help='Subvolumes to ingore or analyze') 472 | args=parser.parse_args() 473 | 474 | #find subvolumes to parse, make sure -r subvolume stays first 475 | parse_trees=[5] 476 | if args.root!=5: 477 | parse_trees=[args.root,5] 478 | fs = btrfs.FileSystem(args.path) 479 | for subvol in fs.subvolumes(): 480 | if subvol.key.objectid != args.root: 481 | parse_trees.append(subvol.key.objectid) 482 | 483 | #these are the subvolumes specified by the user, these will be either ignored 484 | #or all the other subvolumes will be ingored 485 | special_subvolumes=set(args.subvolume) 486 | 487 | #if no argument specified then assume that the user wanted to ingore the speficied subvolumes 488 | if args.ignore == False and args.only== False: 489 | args.ignore=True 490 | 491 | #remove the unneeded subvolumes 492 | if args.ignore: 493 | for item in special_subvolumes: 494 | try: 495 | parse_trees.remove(item) 496 | except: 497 | pass 498 | else: 499 | for tree in parse_trees[:]: 500 | if tree not in special_subvolumes: 501 | parse_trees.remove(tree) 502 | 503 | data_tree=TreeWrapper() 504 | 505 | #move the root subvolume in the end 506 | #older subvolumes must be first 507 | changed_snapshots = deque(parse_trees) 508 | changed_snapshots.rotate(-1) 509 | parse_trees=list(changed_snapshots) 510 | data_tree.add_snapshots(parse_trees) 511 | 512 | #parse the trees from newer to older 513 | parse_trees=list(reversed(parse_trees)) 514 | print("Subvolumes to parse:",parse_trees) 515 | 516 | queue = multiprocessing.JoinableQueue() 517 | barrier = multiprocessing.Barrier(len(parse_trees)) 518 | lock = multiprocessing.RLock() 519 | semaphore = multiprocessing.BoundedSemaphore(args.cpus) 520 | list_of_producers=[] 521 | for tree in parse_trees: 522 | #process=multiprocessing.Process(target=disk_parse_queue,name="Sub"+str(tree), args=(semaphore,queue,args.path,tree),daemon=True) 523 | process=multiprocessing.Process(target=disk_parse_queue,name="Sub"+str(tree), args=(semaphore,lock,barrier,queue,args.path,tree),daemon=True) 524 | list_of_producers.append(process) 525 | process.start() 526 | 527 | while True: 528 | res=queue.get() 529 | queue.task_done() 530 | if res !=None: 531 | if args.files: 532 | data_tree.add(res[4],res[0],res[1],res[2],res[3]) 533 | else: 534 | data_tree.add(res[4],res[0],res[1],res[2],0) 535 | else: 536 | break 537 | 538 | print("Parsing Done") 539 | for process in list_of_producers: 540 | process.join() 541 | 542 | data_tree.transform() 543 | unique_sum=0 544 | unique_data,files=data_tree.find_unique(fs,args.files) 545 | #if unique analysis is only needed, do not calculate differences 546 | if args.unique: 547 | current_data=Counter() 548 | previous_data=Counter() 549 | else: 550 | current_data=data_tree.find_snapshot_size_to_current() 551 | previous_data=data_tree.find_snapshot_size_to_previous() 552 | print(" Unique File Extents Extents added ontop Extents added ontop of") 553 | print(" per subvolume of previous subvolume current(act) subvolume") 554 | print("---------------------|---------------------|----------------------") 555 | print("SubvolumId Size Size Size") 556 | for snapshot in parse_trees: 557 | print("{:>10} {:>10} {:>10} {:>10}".format(snapshot,btrfs.utils.pretty_size(unique_data[snapshot]),btrfs.utils.pretty_size(previous_data[snapshot]),btrfs.utils.pretty_size(current_data[snapshot]))) 558 | #print(files[snapshot]) 559 | unique_sum+=unique_data[snapshot] 560 | total_data=len(data_tree) 561 | print("Unique Data size of subvolumes:",btrfs.utils.pretty_size(unique_sum),"Total size:",btrfs.utils.pretty_size(total_data),"Volatility:","{:.2%}".format(unique_sum/total_data)) 562 | if args.files: 563 | print() 564 | print("Possible Unique Files:") 565 | for file,myset in files.items(): 566 | print(file,":",myset) 567 | 568 | if __name__ == '__main__': 569 | main() 570 | --------------------------------------------------------------------------------