[PATCH][BTRFS-PROGS][V6] btrfs filesystem df

[PATCH][BTRFS-PROGS][V6] btrfs filesystem df

[Goffredo Baroncelli]

Hi Chris,

this serie of patches updated the command "btrfs filesystem
df". I update this command because it is not so easy to get
the information about the disk usage from the command "fi df" and "fi show".
This patch was the result of some discussions on the btrfs 
mailing list. Many thanks to all the contributors.

from the man page (see 2nd patch):

[...]
The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
[...]

$ ./btrfs filesystem df --help
usage: btrfs filesystem disk-usage [-k] <path> [<path>..]

    Show space usage information for a mount point(s).

    -k  Set KB (1024 bytes) as unit

$ ./btrfs filesystem df /
Path: /
Summary:
  Disk_size:                 72.57GB
  Disk_allocated:            25.10GB
  Disk_unallocated:          47.48GB
  Logical_size:              23.06GB
  Used:                      11.01GB
  Free_(Estimated):          55.66GB    (Max: 59.52GB, Min: 35.78GB)
  Data_to_disk_ratio:           92 %

Allocated_area:
  Type        Mode       Size_(disk)    Size_(logical)          Used
  Data        Single         21.01GB           21.01GB       12.77GB
  System      DUP            80.00MB           40.00MB        4.00KB
  System      Single          4.00MB            4.00MB          0.00
  Metadata    DUP             4.00GB            2.00GB      709.63MB
  Metadata    Single          8.00MB            8.00MB          0.00

Where:
        Disk_size                       -> sum of sizes of teh disks
        Disk_allocated                  -> sum of chunk sizes
        Disk_unallocated                -> Disk_size - Disk_allocated
        Logical_size                    -> sum of logical area sizes
        Used                            -> logical area used
        Free_(Estimated)                -> on the basis of allocated
                                           chunk, an estrapolation of
                                           the free space
        Data_to_disk_ratio              -> ration between the space occuped
                                           by a chunk and the real space
                                           available ( due to duplication
                                           and/or RAID level)
        Type				-> kind of chunk
        Mode                            -> allocation policy of a chunk
        Size_(disk)                     -> area of disk(s) occuped by the
                                           chunk (see it as raw space used)
        Size_(logical)                  -> logical area size of the chunk
        Used                            -> portion of the logical area
                                           used by the filesystem



You can pull this change from
   http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
branch
   disk_free

Please pull.

Signed-off-by: Goffredo Baroncelli <kreijack@gmail.com>

BR
Goffredo Baroncelli

Changelog:
V5->V6		Th V5 was a wrong patch, please discard it.
V4->V5		Add a close(fd) to avoid file descriptor leaking
V3->V4		Removed the switch -d -s from getopt(), aligned the
		column Size_(logical), renamed the fields:
		- Details -> Allocated_area
		- Chunk_type -> Type
V2->V3          Removed the options '-s' and '-d'; replaced Chunk-size 
                and Logical-size with Size_(disk) and Size_(logical).
                Update the man page.
V1->V2          Uses getopt(); replace "-" with "_"; change the behaviour
                of the switches '-s' and '-d'.
V0->V1          Change the name of command from disk-usage to df

[PATCH 1/2] Update btrfs filesystem df command

[Goffredo Baroncelli]

From: Goffredo Baroncelli <kreijack@inwind.it>

The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
---
 cmds-filesystem.c |  311 ++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 260 insertions(+), 51 deletions(-)

diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index 9c43d35..fceba0e 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -22,6 +22,7 @@
 #include <errno.h>
 #include <uuid/uuid.h>
 #include <ctype.h>
+#include <sys/vfs.h>
 
 #include "kerncompat.h"
 #include "ctree.h"
@@ -39,25 +40,86 @@ static const char * const filesystem_cmd_group_usage[] = {
 	NULL
 };
 
-static const char * const cmd_df_usage[] = {
-	"btrfs filesystem df <path>",
-	"Show space usage information for a mount point",
-	NULL
-};
+static u64 disk_size( char *path){
+	struct statfs	sfs;
+
+	if( statfs(path, &sfs) < 0 )
+		return 0;
+	else
+		return sfs.f_bsize * sfs.f_blocks;
+
+}
+
+static void **strings_to_free=0;
+static int count_string_to_free=0;
+
+static void add_strings_to_free(char *s)
+{
+	int  size;
+
+	size = sizeof(void*) * ++count_string_to_free;
+	strings_to_free = realloc( strings_to_free, size);
+
+	/* if we don't have enough memory, we have more serius
+	   problem than that a wrong handling of not enough memory */
+	if(!strings_to_free){
+		fprintf(stderr, "add_string_to_free(): Not enough memory\n");
+		strings_to_free=0;
+		count_string_to_free=0;
+	}
+
+	strings_to_free[count_string_to_free-1] = s;
+}
+
+static void free_strings_to_free( )
+{
+	int	i;
+	for( i = 0 ; i < count_string_to_free ; i++ )
+		free(strings_to_free[i]);
+
+	free(strings_to_free);
+
+	strings_to_free=0;
+	count_string_to_free=0;
+}
+
+#define DF_SHOW_SUMMARY 	(1<<1)
+#define DF_SHOW_DETAIL		(1<<2)
+#define DF_HUMAN_UNIT		(1<<3)
+
+static char *df_pretty_sizes(u64 size, int mode)
+{
+	char *s;
+
+	if( mode & DF_HUMAN_UNIT ){
+		s = pretty_sizes(size);
+		if(!s) return NULL;
+	} else {
+		s = malloc(20);
+		if(!s) return NULL;
+		sprintf(s, "%llu", size/1024);
+	}
+
+	add_strings_to_free(s);
+	return s;
+}
+
 
-static int cmd_df(int argc, char **argv)
+static int _cmd_disk_free(char *path, int mode)
 {
 	struct btrfs_ioctl_space_args *sargs, *sargs_orig;
 	u64 count = 0, i;
 	int ret;
 	int fd;
-	int e;
-	char *path;
-
-	if (check_argc_exact(argc, 2))
-		usage(cmd_df_usage);
-
-	path = argv[1];
+	int e, width, width_sl;
+	u64  total_disk;		/* filesystem size == sum of
+					   disks sizes */
+	u64  total_chunks;		/* sum of chunks sizes on disk(s) */
+	u64  total_used;		/* logical space used */
+	u64  total_free;		/* logical space un-used */
+	double K;
+	char	*rpath;
+	
 
 	fd = open_file_or_dir(path);
 	if (fd < 0) {
@@ -102,65 +164,212 @@ static int cmd_df(int argc, char **argv)
 
 	ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
 	e = errno;
+	close(fd);
+
 	if (ret) {
 		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
 			path, strerror(e));
-		close(fd);
 		free(sargs);
 		return ret;
 	}
 
-	for (i = 0; i < sargs->total_spaces; i++) {
-		char description[80];
-		char *total_bytes;
-		char *used_bytes;
-		int written = 0;
-		u64 flags = sargs->spaces[i].flags;
+	total_disk = disk_size(path);
+	e = errno;
+	if( total_disk == 0 ){
+		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
+			path, strerror(e));
+		free(sargs);
+		return 19;
+	}
+		
+	total_chunks = total_used = total_free = 0;
 
-		memset(description, 0, 80);
+	for (i = 0; i < sargs->total_spaces; i++) {
+		int  ratio=1;
+		u64  allocated;
 
-		if (flags & BTRFS_BLOCK_GROUP_DATA) {
-			if (flags & BTRFS_BLOCK_GROUP_METADATA) {
-				snprintf(description, 14, "%s",
-					 "Data+Metadata");
-				written += 13;
-			} else {
-				snprintf(description, 5, "%s", "Data");
-				written += 4;
-			}
-		} else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) {
-			snprintf(description, 7, "%s", "System");
-			written += 6;
-		} else if (flags & BTRFS_BLOCK_GROUP_METADATA) {
-			snprintf(description, 9, "%s", "Metadata");
-			written += 8;
-		}
+		u64 flags = sargs->spaces[i].flags;
 
 		if (flags & BTRFS_BLOCK_GROUP_RAID0) {
-			snprintf(description+written, 8, "%s", ", RAID0");
-			written += 7;
+			ratio=1;
 		} else if (flags & BTRFS_BLOCK_GROUP_RAID1) {
-			snprintf(description+written, 8, "%s", ", RAID1");
-			written += 7;
+			ratio=2;
 		} else if (flags & BTRFS_BLOCK_GROUP_DUP) {
-			snprintf(description+written, 6, "%s", ", DUP");
-			written += 5;
+			ratio=2;
 		} else if (flags & BTRFS_BLOCK_GROUP_RAID10) {
-			snprintf(description+written, 9, "%s", ", RAID10");
-			written += 8;
+			ratio=2;
+		} else {
+			ratio=1;
 		}
 
-		total_bytes = pretty_sizes(sargs->spaces[i].total_bytes);
-		used_bytes = pretty_sizes(sargs->spaces[i].used_bytes);
-		printf("%s: total=%s, used=%s\n", description, total_bytes,
-		       used_bytes);
+		allocated = sargs->spaces[i].total_bytes * ratio;
+
+		total_chunks += allocated;
+		total_used += sargs->spaces[i].used_bytes;
+		total_free += (sargs->spaces[i].total_bytes - 
+					sargs->spaces[i].used_bytes);
+
 	}
-	close(fd);
+	K = ((double)total_used + (double)total_free) /
+	                (double)total_chunks;
+
+	if( mode & DF_HUMAN_UNIT ){
+		width = 14;
+		width_sl = 18;
+	} else {
+		width = 18;
+		width_sl = 18;
+	}
+
+	rpath = realpath(path, 0);
+	printf("Path: %s\n", rpath);
+	free(rpath);
+
+	if( mode & DF_SHOW_SUMMARY ){
+		printf("Summary:\n");
+		printf("  Disk_size:\t\t%*s\n", width,
+			df_pretty_sizes(total_disk, mode));
+		printf("  Disk_allocated:\t%*s\n", width,
+			df_pretty_sizes(total_chunks, mode));
+		printf("  Disk_unallocated:\t%*s\n", width,
+			df_pretty_sizes(total_disk-total_chunks, mode));
+		printf("  Logical_size:\t\t%*s\n", width,
+			df_pretty_sizes(total_used+total_free, mode));
+		printf("  Used:\t\t\t%*s\n", width, 
+			df_pretty_sizes(total_used, mode));
+		printf("  Free_(Estimated):\t%*s\t(Max: %s, min: %s)\n",
+			width, 
+			df_pretty_sizes((u64)(K*total_disk-total_used),  mode),
+			df_pretty_sizes(total_disk-total_chunks+total_free, 
+				mode ),
+			df_pretty_sizes((total_disk-total_chunks)/2+total_free, 
+				mode ));
+		printf("  Data_to_disk_ratio:\t%*.0f %%\n",
+			width-2, K*100);
+	}
+
+	if( ( mode & DF_SHOW_DETAIL ) && ( mode & DF_SHOW_SUMMARY ) )
+		printf("\n");
+
+	if( mode & DF_SHOW_DETAIL ){
+		/* Remember: the terminals have maximum 80 columns
+		   do not believe to who says otherwise */
+		printf("Allocated_area:\n");
+		printf("  %-12s%-8s%*s%*s%*s\n",
+			"Type", 
+			"Mode",
+			width, "Size_(disk)", 
+			width_sl, "Size_(logical)", 
+			width, "Used"
+		);
+
+		for (i = 0; i < sargs->total_spaces; i++) {
+			char *description="";
+			int  ratio=1;
+			char *r_mode;
+			u64 allocated;
+
+			u64 flags = sargs->spaces[i].flags;
+
+			if (flags & BTRFS_BLOCK_GROUP_DATA) {
+				if (flags & BTRFS_BLOCK_GROUP_METADATA){
+					description = "Data+M.data";
+				} else {
+					description = "Data";
+				}
+			} else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) {
+				description = "System";
+			} else if (flags & BTRFS_BLOCK_GROUP_METADATA) {
+				description = "Metadata";
+			}
+
+			if (flags & BTRFS_BLOCK_GROUP_RAID0) {
+				r_mode = "RAID0";
+				ratio=1;
+			} else if (flags & BTRFS_BLOCK_GROUP_RAID1) {
+				r_mode = "RAID1";
+				ratio=2;
+			} else if (flags & BTRFS_BLOCK_GROUP_DUP) {
+				r_mode = "DUP";
+				ratio=2;
+			} else if (flags & BTRFS_BLOCK_GROUP_RAID10) {
+				r_mode = "RAID10";
+				ratio=2;
+			} else {
+				r_mode = "Single";
+				ratio=1;
+			}
+
+			allocated = sargs->spaces[i].total_bytes * ratio;
+
+			printf("  %-12s%-8s%*s%*s%*s\n",
+				description,
+				r_mode,
+				width, 
+				df_pretty_sizes(allocated, mode),
+				width_sl,
+				df_pretty_sizes(sargs->spaces[i].total_bytes ,
+				    mode),
+				width,
+				df_pretty_sizes(sargs->spaces[i].used_bytes, 
+						mode));
+
+		}
+	}
+	free_strings_to_free();
 	free(sargs);
 
 	return 0;
 }
 
+static const char * const cmd_disk_free_usage[] = {
+	"btrfs filesystem df [-k] <path> [<path>..]",
+	"Show space usage information for a mount point(s).",
+	"",
+	"-k\tSet KB (1024 bytes) as unit",
+	NULL
+};
+
+static int cmd_disk_free(int argc, char **argv)
+{
+
+	int 	flags=DF_SHOW_SUMMARY|DF_SHOW_DETAIL|DF_HUMAN_UNIT;
+	int	i, more_than_one=0;
+
+	optind = 1;
+	while(1){
+		char	c = getopt(argc, argv, "k");
+		if(c<0)
+			break;
+		switch(c){
+			case 'k':
+				flags &= ~DF_HUMAN_UNIT;
+				break;
+			default:
+				usage(cmd_disk_free_usage);
+		}
+	}
+
+	if (check_argc_min(argc - optind, 1)){
+		usage(cmd_disk_free_usage);
+		return 21;
+	}
+
+	for(i=optind; i< argc ; i++){
+		int r;
+		if(more_than_one)
+			printf("\n");
+		r = _cmd_disk_free(argv[i], flags);
+		if( r ) return r;
+		more_than_one=1;
+
+	}
+
+	return 0;
+}	
+	
+
+	
 static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
 {
 	char uuidbuf[37];
@@ -537,7 +746,7 @@ static int cmd_label(int argc, char **argv)
 
 const struct cmd_group filesystem_cmd_group = {
 	filesystem_cmd_group_usage, NULL, {
-		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
+		{ "df", cmd_disk_free, cmd_disk_free_usage, NULL, 0 },
 		{ "show", cmd_show, cmd_show_usage, NULL, 0 },
 		{ "sync", cmd_sync, cmd_sync_usage, NULL, 0 },
 		{ "defragment", cmd_defrag, cmd_defrag_usage, NULL, 0 },
-- 
1.7.10.4

[PATCH 2/2] Update help page

[Goffredo Baroncelli]

From: Goffredo Baroncelli <kreijack@inwind.it>

---
 man/btrfs.8.in |  100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 100 insertions(+)

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 9222580..7048273 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -27,6 +27,8 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
 .PP
+\fBbtrfs\fP \fBfilesystem df\fP\fI [-k] \fIpath [path..]\fR\fP
+.PP
 \fBbtrfs\fP \fBsubvolume find-new\fP\fI <subvolume> <last_gen>\fP
 .PP
 \fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
@@ -242,6 +244,104 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
+\fBfilesystem df\fP [-k] \fIpath [path..]\fR
+
+Show space usage information for a mount point.
+
+\fIOptions\fP
+
+\fB-k\fP Set KB (1024 bytes) as unit
+
+\fIUsage information\fP
+
+.\"
+.\" this section is extract from 
+.\"	http://en.wikipedia.org/wiki/Btrfs#Chunk_and_device_trees
+The disk(s) of a btrfs filesystem are divided into chunks of 256 MB or more. 
+Chunks may be mirrored or striped across multiple devices, depending by
+the allocation policy.
+The mirroring/striping arrangement is transparent to the rest of the 
+file system, which simply sees the single, logical address space that 
+chunks are mapped into.
+Chunks are allocated on demand. In the default allocation policy 
+the data chunks are not duplicated and the metadata chunks
+are duplicated. This default can be changed during the filesystem
+creation, and in general the chunks allocation policy may change
+during the filesystem life. 
+
+Depending by the allocation policy a chunk may require a space on
+the disk greater than the logical space that it provides. E.g.
+a chunk DUPlicated or with a RAID1/RAID10 level 
+requires a space on the disk 
+two times greater than the logical space provided. 
+Different RAID levels
+have a different ratio disk-usage / logical space offered.
+
+Normally the file contents are stored in the Data chunks; however
+small files (which fit into a btree leaf) are stored in the 
+metadata chunks. So the computation of the \fIfree space\fP 
+and \fIused space\fP
+is complex: depending by the file size different 
+allocation policies are used.
+
+The command \fBbtrfs filesystem df\fP is used to query the status
+of the chunks, how many space on the disk(s) are used by the chunks, 
+how many space are available in the chunks, and an estimation of the free
+space of the filesystem.
+The output of the command \fBbtrfs filesystem df\fP shows:
+
+.RS
+.IP \fBDisk\ size\fP
+the total size of the disks which compose the filesystem.
+
+.IP \fBDisk\ allocated\fP\ or\ \fBSize_(disk)\fP
+the size of the area of the disks used by the chunks.
+
+.IP \fBDisk\ unallocated\fP 
+the size of the area of the disks which is free (i.e.
+the differences of the values above).
+
+.IP \fBLogical\ size\fP\ or\ \fBSize_(logical)\fP
+the available logical space of chunk. 
+
+.IP \fBUsed\fP
+the portion of the logical space used by the file and metadata.
+
+.IP \fBFree\ (estimated)\fP
+the estimated free space available. The evaluation 
+cannot be rigorous because it depends by the allocation policy (DUP,Single,
+RAID1...) of the metadata and data chunks. If every chunks is stored as
+"Single" the sum of the \fBfree (estimated)\fP space and the \fBused\fP 
+space  is equal to the \fBdisk size\fP.
+Otherwise if all the chunk are mirrored (raid1 or raid10) or duplicated
+the sum of the \fBfree (estimated)\fP space and the \fBused\fP space is
+half of the \fBdisk size\fP. Normally the \fBfree (estimated)\fP is between
+these two limits.
+
+.IP \fBData\ to\ disk\ ratio\fP
+the ratio betwen the \fBlogical size\fP and the \fBdisk allocated\fP.
+
+.IP \fBMode\fP
+the kind of allocation policy used by the chunk (e.g. DUPlicated,
+RAID1, RAID10, Single....)
+
+.IP \fBType\fP
+the kind of chunk (Data, Metdata, System...)
+
+.RE
+.RS
+\fINOTE\fP
+
+When a chunk is allocated, its disk-area is used and its allocation
+policy is fixed.
+A rebalance operation could rearrange the chunks, moving data in the chunks
+and resizing the allocated chunks. This causes the change of all the values 
+discussed above, with the exception of the \fBused\fP and 
+\fBdisk size\fP values.
+
+.RE
+.TP
+
 \fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
 Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
 \fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
-- 
1.7.10.4

Re: [PATCH][BTRFS-PROGS][V6] btrfs filesystem df

[Martin Steigerwald]

Am Samstag, 13. Oktober 2012 schrieb Goffredo Baroncelli:
> Hi Chris,
> 
> this serie of patches updated the command "btrfs filesystem
> df". I update this command because it is not so easy to get
> the information about the disk usage from the command "fi df" and "fi show".
> This patch was the result of some discussions on the btrfs 
> mailing list. Many thanks to all the contributors.
> 
> from the man page (see 2nd patch):
> 
> [...]
> The  command  btrfs  filesystem  df is used to query the
> status of the chunks, how many space on the disk(s) are used  by
> the  chunks,  how many space are available in the chunks, and an
> estimation of the free space of the filesystem.
> [...]
> 
> $ ./btrfs filesystem df --help
> usage: btrfs filesystem disk-usage [-k] <path> [<path>..]
> 
>     Show space usage information for a mount point(s).
> 
>     -k  Set KB (1024 bytes) as unit
> 
> $ ./btrfs filesystem df /
> Path: /
> Summary:
>   Disk_size:                 72.57GB
>   Disk_allocated:            25.10GB
>   Disk_unallocated:          47.48GB
>   Logical_size:              23.06GB
>   Used:                      11.01GB
>   Free_(Estimated):          55.66GB    (Max: 59.52GB, Min: 35.78GB)
>   Data_to_disk_ratio:           92 %
> 
> Allocated_area:
>   Type        Mode       Size_(disk)    Size_(logical)          Used
>   Data        Single         21.01GB           21.01GB       12.77GB
>   System      DUP            80.00MB           40.00MB        4.00KB
>   System      Single          4.00MB            4.00MB          0.00
>   Metadata    DUP             4.00GB            2.00GB      709.63MB
>   Metadata    Single          8.00MB            8.00MB          0.00
> 
> Where:
>         Disk_size                       -> sum of sizes of teh disks
>         Disk_allocated                  -> sum of chunk sizes
>         Disk_unallocated                -> Disk_size - Disk_allocated
>         Logical_size                    -> sum of logical area sizes
>         Used                            -> logical area used
>         Free_(Estimated)                -> on the basis of allocated
>                                            chunk, an estrapolation of
>                                            the free space
>         Data_to_disk_ratio              -> ration between the space occuped
>                                            by a chunk and the real space
>                                            available ( due to duplication
>                                            and/or RAID level)
>         Type				-> kind of chunk
>         Mode                            -> allocation policy of a chunk
>         Size_(disk)                     -> area of disk(s) occuped by the
>                                            chunk (see it as raw space used)
>         Size_(logical)                  -> logical area size of the chunk
>         Used                            -> portion of the logical area
>                                            used by the filesystem

Works nicely:

merkaba:/home/martin/[…]/btrfs-progs-unstable> ./btrfs fi df /
Path: /
Summary:
  Disk_size:                   18.62GB
  Disk_allocated:              18.62GB
  Disk_unallocated:               0.00
  Logical_size:                16.87GB
  Used:                        12.53GB
  Free_(Estimated):             4.34GB  (Max: 4.34GB, min: 4.34GB)
  Data_to_disk_ratio:             91 %

Allocated_area:
  Type        Mode       Size_(disk)    Size_(logical)          Used
  Data        Single         15.10GB           15.10GB       11.84GB
  System      DUP            16.00MB            8.00MB        4.00KB
  System      Single          4.00MB            4.00MB          0.00
  Metadata    DUP             3.50GB            1.75GB      696.70MB
  Metadata    Single          8.00MB            8.00MB          0.00

Tested-By: Martin Steigerwald <martin@lichtvoll.de>

Thanks,
Martin

> You can pull this change from
>    http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
> branch
>    disk_free
> 
> Please pull.
> 
> Signed-off-by: Goffredo Baroncelli <kreijack@gmail.com>
> 
> BR
> Goffredo Baroncelli
> 
> Changelog:
> V5->V6		Th V5 was a wrong patch, please discard it.
> V4->V5		Add a close(fd) to avoid file descriptor leaking
> V3->V4		Removed the switch -d -s from getopt(), aligned the
> 		column Size_(logical), renamed the fields:
> 		- Details -> Allocated_area
> 		- Chunk_type -> Type
> V2->V3          Removed the options '-s' and '-d'; replaced Chunk-size 
>                 and Logical-size with Size_(disk) and Size_(logical).
>                 Update the man page.
> V1->V2          Uses getopt(); replace "-" with "_"; change the behaviour
>                 of the switches '-s' and '-d'.
> V0->V1          Change the name of command from disk-usage to df
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 


-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7

[PATCH][BTRFS-PROGS][V4] btrfs filesystem df

[Goffredo Baroncelli]

Hi Chris,

this serie of patches updated the command "btrfs filesystem
df". I update this command because it is not so easy to get
the information about the disk usage from the command "fi df" and "fi show".
This patch was the result of some discussions on the btrfs 
mailing list. Many thanks to all the contributors.

from the man page (see 2nd patch):

[...]
The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
[...]

$ ./btrfs filesystem df --help
usage: btrfs filesystem disk-usage [-k] <path> [<path>..]

    Show space usage information for a mount point(s).

    -k  Set KB (1024 bytes) as unit

$ ./btrfs filesystem df /
Path: /
Summary:
  Disk_size:                 72.57GB
  Disk_allocated:            25.10GB
  Disk_unallocated:          47.48GB
  Logical_size:              23.06GB
  Used:                      11.01GB
  Free_(Estimated):          55.66GB    (Max: 59.52GB, Min: 35.78GB)
  Data_to_disk_ratio:           92 %

Allocated_area:
  Type        Mode       Size_(disk)    Size_(logical)          Used
  Data        Single         21.01GB           21.01GB       12.77GB
  System      DUP            80.00MB           40.00MB        4.00KB
  System      Single          4.00MB            4.00MB          0.00
  Metadata    DUP             4.00GB            2.00GB      709.63MB
  Metadata    Single          8.00MB            8.00MB          0.00

Where:
        Disk_size                       -> sum of sizes of teh disks
        Disk_allocated                  -> sum of chunk sizes
        Disk_unallocated                -> Disk_size - Disk_allocated
        Logical_size                    -> sum of logical area sizes
        Used                            -> logical area used
        Free_(Estimated)                -> on the basis of allocated
                                           chunk, an estrapolation of
                                           the free space
        Data_to_disk_ratio              -> ration between the space occuped
                                           by a chunk and the real space
                                           available ( due to duplication
                                           and/or RAID level)
        Type				-> kind of chunk
        Mode                            -> allocation policy of a chunk
        Size_(disk)                     -> area of disk(s) occuped by the
                                           chunk (see it as raw space used)
        Size_(logical)                  -> logical area size of the chunk
        Used                            -> portion of the logical area
                                           used by the filesystem



You can pull this change from
   http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
branch
   disk_free

Please pull.

BR
Goffredo Baroncelli

Changelog:
V3->V4		Removed the switch -d -s from getopt(), aligned the
		column Size_(logical), renamed the fields:
		- Details -> Allocated_area
		- Chunk_type -> Type
V2->V3          Removed the options '-s' and '-d'; replaced Chunk-size 
                and Logical-size with Size_(disk) and Size_(logical).
                Update the man page.
V1->V2          Uses getopt(); replace "-" with "_"; change the behaviour
                of the switches '-s' and '-d'.
V0->V1          Change the name of command from disk-usage to df

[PATCH 2/2] Update help page

[Goffredo Baroncelli]

From: Goffredo Baroncelli <kreijack@inwind.it>

---
 man/btrfs.8.in |  100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 100 insertions(+)

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 4b0a9f9..ecd0916 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -27,6 +27,8 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
 .PP
+\fBbtrfs\fP \fBfilesystem df\fP\fI [-k] \fIpath [path..]\fR\fP
+.PP
 \fBbtrfs\fP \fBsubvolume find-new\fP\fI <subvolume> <last_gen>\fP
 .PP
 \fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
@@ -214,6 +216,104 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
+\fBfilesystem df\fP [-k] \fIpath [path..]\fR
+
+Show space usage information for a mount point.
+
+\fIOptions\fP
+
+\fB-k\fP Set KB (1024 bytes) as unit
+
+\fIUsage information\fP
+
+.\"
+.\" this section is extract from 
+.\"	http://en.wikipedia.org/wiki/Btrfs#Chunk_and_device_trees
+The disk(s) of a btrfs filesystem are divided into chunks of 256 MB or more. 
+Chunks may be mirrored or striped across multiple devices, depending by
+the allocation policy.
+The mirroring/striping arrangement is transparent to the rest of the 
+file system, which simply sees the single, logical address space that 
+chunks are mapped into.
+Chunks are allocated on demand. In the default allocation policy 
+the data chunks are not duplicated and the metadata chunks
+are duplicated. This default can be changed during the filesystem
+creation, and in general the chunks allocation policy may change
+during the filesystem life. 
+
+Depending by the allocation policy a chunk may require a space on
+the disk greater than the logical space that it provides. E.g.
+a chunk DUPlicated or with a RAID1/RAID10 level 
+requires a space on the disk 
+two times greater than the logical space provided. 
+Different RAID levels
+have a different ratio disk-usage / logical space offered.
+
+Normally the file contents are stored in the Data chunks; however
+small files (which fit into a btree leaf) are stored in the 
+metadata chunks. So the computation of the \fIfree space\fP 
+and \fIused space\fP
+is complex: depending by the file size different 
+allocation policies are used.
+
+The command \fBbtrfs filesystem df\fP is used to query the status
+of the chunks, how many space on the disk(s) are used by the chunks, 
+how many space are available in the chunks, and an estimation of the free
+space of the filesystem.
+The output of the command \fBbtrfs filesystem df\fP shows:
+
+.RS
+.IP \fBDisk\ size\fP
+the total size of the disks which compose the filesystem.
+
+.IP \fBDisk\ allocated\fP\ or\ \fBSize_(disk)\fP
+the size of the area of the disks used by the chunks.
+
+.IP \fBDisk\ unallocated\fP 
+the size of the area of the disks which is free (i.e.
+the differences of the values above).
+
+.IP \fBLogical\ size\fP\ or\ \fBSize_(logical)\fP
+the available logical space of chunk. 
+
+.IP \fBUsed\fP
+the portion of the logical space used by the file and metadata.
+
+.IP \fBFree\ (estimated)\fP
+the estimated free space available. The evaluation 
+cannot be rigorous because it depends by the allocation policy (DUP,Single,
+RAID1...) of the metadata and data chunks. If every chunks is stored as
+"Single" the sum of the \fBfree (estimated)\fP space and the \fBused\fP 
+space  is equal to the \fBdisk size\fP.
+Otherwise if all the chunk are mirrored (raid1 or raid10) or duplicated
+the sum of the \fBfree (estimated)\fP space and the \fBused\fP space is
+half of the \fBdisk size\fP. Normally the \fBfree (estimated)\fP is between
+these two limits.
+
+.IP \fBData\ to\ disk\ ratio\fP
+the ratio betwen the \fBlogical size\fP and the \fBdisk allocated\fP.
+
+.IP \fBMode\fP
+the kind of allocation policy used by the chunk (e.g. DUPlicated,
+RAID1, RAID10, Single....)
+
+.IP \fBType\fP
+the kind of chunk (Data, Metdata, System...)
+
+.RE
+.RS
+\fINOTE\fP
+
+When a chunk is allocated, its disk-area is used and its allocation
+policy is fixed.
+A rebalance operation could rearrange the chunks, moving data in the chunks
+and resizing the allocated chunks. This causes the change of all the values 
+discussed above, with the exception of the \fBused\fP and 
+\fBdisk size\fP values.
+
+.RE
+.TP
+
 \fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
 Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
 \fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
-- 
1.7.10.4

[PATCH][BTRFS-PROGS][V3] btrfs filesystem df

[Goffredo Baroncelli]

Hi Chris,

this serie of patches updated the command "btrfs filesystem
df". I update this command because it is not so easy to get
the information about the disk usage from the command "fi df" and "fi show".
This patch was the result of some discussions on the btrfs 
mailing list. Many thanks to all the contributors.

>From the man page (see 2nd patch):

[...]
The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
[...]

$ ./btrfs filesystem df --help
usage: btrfs filesystem disk-usage [-k] <path> [<path>..]

    Show space usage information for a mount point(s).

    -k  Set KB (1024 bytes) as unit

$ ./btrfs filesystem df /
Path: /
Summary:
  Disk_size:                 72.57GB
  Disk_allocated:            25.10GB
  Disk_unallocated:          47.48GB
  Logical_size:              23.06GB
  Used:                      11.01GB
  Free_(Estimated):          55.66GB    (Max: 59.52GB, Min: 35.78GB)
  Data_to_disk_ratio:           92 %

Details:
  Chunk_type  Mode     Size_(disk) Size_(logical)     Used
  Data        Single       21.01GB      21.01GB     10.34GB
  System      DUP          80.00MB      40.00MB      4.00KB
  System      Single        4.00MB       4.00MB        0.00
  Metadata    DUP           4.00GB       2.00GB    686.93MB
  Metadata    Single        8.00MB       8.00MB        0.00

Where:
        Disk_size                       -> sum of sizes of teh disks
        Disk_allocated                  -> sum of chunk sizes
        Disk_unallocated                -> Disk_size - Disk_allocated
        Logical_size                    -> sum of logical area sizes
        Used                            -> logical area used
        Free_(Estimated)                -> on the basis of allocated
                                           chunk, an estrapolation of
                                           the free space
        Data_to_disk_ratio              -> ration between the space occuped
                                           by a chunk and the real space
                                           available ( due to duplication
                                           and/or RAID level)
        Chunk_type                      -> kind of chunk
        Mode                            -> allocation policy of a chunk
        Size_(disk)                     -> area of disk(s) occuped by the
                                           chunk (see it as raw space used)
        Size_(logical)                  -> logical area size of the chunk
        Used                            -> portion of the logical area
                                           used by the filesystem



You can pull this change from
   http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
branch
   disk_free

Please pull.

BR
Goffredo Baroncelli

Changelog:
V0->V1          Change the name of command from disk-usage to df
V1->V2          Uses getopt(); replace "-" with "_"; change the behaviour
                of the switches '-s' and '-d'.
V2->V3		Removed the options '-s' and '-d'; replaced Chunk-size 
                and Logical-size with Size_(disk) and Size_(logical).
		Update the man page.

[PATCH 2/2] Update help page

[Goffredo Baroncelli]

From: Goffredo Baroncelli <kreijack@inwind.it>

---
 man/btrfs.8.in |  100 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 100 insertions(+)

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 4b0a9f9..96c9239 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -27,6 +27,8 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
 .PP
+\fBbtrfs\fP \fBfilesystem df\fP\fI [-k] \fIpath [path..]\fR\fP
+.PP
 \fBbtrfs\fP \fBsubvolume find-new\fP\fI <subvolume> <last_gen>\fP
 .PP
 \fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
@@ -214,6 +216,104 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
+\fBfilesystem df\fP [-k] \fIpath [path..]\fR
+
+Show space usage information for a mount point.
+
+\fIOptions\fP
+
+\fB-k\fP Set KB (1024 bytes) as unit
+
+\fIUsage information\fP
+
+.\"
+.\" this section is extract from 
+.\"	http://en.wikipedia.org/wiki/Btrfs#Chunk_and_device_trees
+The disk(s) of a btrfs filesystem are divided into chunks of 256 MB or more. 
+Chunks may be mirrored or striped across multiple devices, depending by
+the allocation policy.
+The mirroring/striping arrangement is transparent to the rest of the 
+file system, which simply sees the single, logical address space that 
+chunks are mapped into.
+Chunks are allocated on demand. In the default allocation policy 
+the data chunks are not duplicated and the metadata chunks
+are duplicated. This default can be changed during the filesystem
+creation, and in general the chunks allocation policy may change
+during the filesystem life. 
+
+Depending by the allocation policy a chunk may require a space on
+the disk greater than the logical space that it provides. E.g.
+a chunk DUPlicated or with a RAID1/RAID10 level 
+requires a space on the disk 
+two times greater than the logical space provided. 
+Different RAID levels
+have a different ratio disk-usage / logical space offered.
+
+Normally the file contents are stored in the Data chunks; however
+small files (which fit into a btree leaf) are stored in the 
+metadata chunks. So the computation of the \fIfree space\fP 
+and \fIused space\fP
+is complex: depending by the file size different 
+allocation policies are used.
+
+The command \fBbtrfs filesystem df\fP is used to query the status
+of the chunks, how many space on the disk(s) are used by the chunks, 
+how many space are available in the chunks, and an estimation of the free
+space of the filesystem.
+The output of the command \fBbtrfs filesystem df\fP shows:
+
+.RS
+.IP \fBDisk\ size\fP
+the total size of the disks which compose the filesystem.
+
+.IP \fBDisk\ allocated\fP\ or\ \fBSize_(disk)\fP
+the size of the area of the disks used by the chunks.
+
+.IP \fBDisk\ unallocated\fP 
+the size of the area of the disks which is free (i.e.
+the differences of the values above).
+
+.IP \fBLogical\ size\fP\ or\ \fBSize_(logical)\fP
+the available logical space of chunk. 
+
+.IP \fBUsed\fP
+the portion of the logical space used by the file and metadata.
+
+.IP \fBFree\ (estimated)\fP
+the estimated free space available. The evaluation 
+cannot be rigorous because it depends by the allocation policy (DUP,Single,
+RAID1...) of the metadata and data chunks. If every chunks is stored as
+"Single" the sum of the \fBfree (estimated)\fP space and the \fBused\fP 
+space  is equal to the \fBdisk size\fP.
+Otherwise if all the chunk are mirrored (raid1 or raid10) or duplicated
+the sum of the \fBfree (estimated)\fP space and the \fBused\fP space is
+half of the \fBdisk size\fP. Normally the \fBfree (estimated)\fP is between
+these two limits.
+
+.IP \fBData\ to\ disk\ ratio\fP
+the ratio betwen the \fBlogical size\fP and the \fBdisk allocated\fP.
+
+.IP \fBMode\fP
+the kind of allocation policy used by the chunk (e.g. DUPlicated,
+RAID1, RAID10, Single....)
+
+.IP \fBChunk\ type\fP
+the kind of chunk (Data, Metdata, System...)
+
+.RE
+.RS
+\fINOTE\fP
+
+When a chunk is allocated, its disk-area is used and its allocation
+policy is fixed.
+A rebalance operation could rearrange the chunks, moving data in the chunks
+and resizing the allocated chunks. This causes the change of all the values 
+discussed above, with the exception of the \fBused\fP and 
+\fBdisk size\fP values.
+
+.RE
+.TP
+
 \fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
 Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
 \fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
-- 
1.7.10.4

[PATCH][BTRFS-PROGS][V2] btrfs filesystem df

[Goffredo Baroncelli]

>From the man page (see 2nd patch):

[...]
The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
[...]

$ ./btrfs filesystem df --help
usage: btrfs filesystem disk-usage [-d|-s][-k] <path> [<path>..]

    Show space usage information for a mount point(s).

    -k  Set KB (1024 bytes) as unit
    -s  Show the summary section only
    -d  Show the detail section only

$ ./btrfs filesystem df /
Path: /
Summary:
  Disk_size:                 72.57GB
  Disk_allocated:            25.10GB
  Disk_unallocated:          47.48GB
  Logical_size:              23.06GB
  Used:                      11.01GB
  Free_(Estimated):          55.66GB    (Max: 59.52GB, Min: 35.78GB)
  Data_to_disk_ratio:           92 %

Details:
  Chunk-type  Mode      Chunk_size Logical_size        Used
  Data        Single       21.01GB      21.01GB     10.34GB
  System      DUP          80.00MB      40.00MB      4.00KB
  System      Single        4.00MB       4.00MB        0.00
  Metadata    DUP           4.00GB       2.00GB    686.93MB
  Metadata    Single        8.00MB       8.00MB        0.00

Where:
        Disk_size                       -> sum of sizes of teh disks
        Disk_allocated                  -> sum of chunk sizes
        Disk_unallocated                -> Disk_size - Disk_allocated
        Logical_size                    -> sum of logical area sizes
        Used                            -> logical area used
        Free_(Estimated)                -> on the basis of allocated
                                           chunk, an estrapolation of
                                           the free space
        Data_to_disk_ratio              -> ration between the space occuped
                                           by a chunk and the real space
                                           available ( due to duplication
                                           and/or RAID level)
        Chunk_type                      -> kind of chunk
        Mode                            -> allocation policy of a chunk
        Chunk_size                      -> area of disk(s) occuped by the
                                           chunk (see it as raw space used)
        Logical_size                    -> logical area size of the chunk
        Used                            -> portion of the logical area
                                           used by the filesystem



You can pull this change from
   http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
branch
   disk_free

Please pull.

BR
Goffredo Baroncelli

Changelog:
V0->V1          Change the name of command from disk-usage to df
V1->V2		Uses getopt(); replace "-" with "_"; change the behaviour
		of the switches '-s' and '-d'.

Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>

[PATCH 2/2] Update help page

[Goffredo Baroncelli]

From: Goffredo Baroncelli <kreijack@inwind.it>

---
 man/btrfs.8.in |   94 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 4b0a9f9..0db588f 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -27,6 +27,8 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
 .PP
+\fBbtrfs\fP \fBfilesystem df\fP\fI [-s|-d][-k] \fIpath [path..]\fR\fP
+.PP
 \fBbtrfs\fP \fBsubvolume find-new\fP\fI <subvolume> <last_gen>\fP
 .PP
 \fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
@@ -214,6 +216,98 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
+\fBfilesystem df\fP [-s|-d][-k] \fIpath [path..]\fR
+
+Show space usage information for a mount point.
+
+\fIOptions\fP
+
+\fB-k\fP Set KB (1024 bytes) as unit
+
+\fB-s\fP Show the summary section only
+
+\fB-d\fP Show the detail section only
+
+\fIUsage information\fP
+
+.\"
+.\" this section is extract from 
+.\"	http://en.wikipedia.org/wiki/Btrfs#Chunk_and_device_trees
+The disk(s) of a btrfs filesystem are divided into chunks of 256 MB or more. 
+Chunks may be mirrored or striped across multiple devices, depending by
+the allocation policy.
+The mirroring/striping arrangement is transparent to the rest of the 
+file system, which simply sees the single, logical address space that 
+chunks are mapped into.
+Chunks are allocated on demand. In the default allocation policy 
+the data chunks are not duplicated and the metadata chunks
+are duplicated. This default can be changed during the filesystem
+creation, and in general the chunks allocation policy may change
+during the filesystem life. 
+
+A chunk DUPlicated or with a RAID1/RAID10 level 
+requires a space two time greater than the logical one. Different RAID levels
+have a different ratio disk-usage / logical space offered.
+
+Because some files (the small ones) are stored in the 
+metadata chunks the computation of the \fIfree space\fP and \fIused space\fP
+is complex: depending by the file size different allocation policies are used.
+
+The command \fBbtrfs filesystem df\fP is used to query the status
+of the chunks, how many space on the disk(s) are used by the chunks, 
+how many space are available in the chunks, and an estimation of the free
+space of the filesystem.
+The output of the command \fBbtrfs filesystem df\fP shows:
+
+.RS
+.IP Disk\ size 
+the total size of the disks which compose the filesystem.
+
+.IP Disk\ allocated 
+the size of the area of the disks used by the chunks.
+
+.IP Disk\ unallocated 
+the size of the area of the disks which is free (i.e.
+the differences of the values above).
+
+.IP Logical\ size 
+the available logical space of chunk. 
+
+.IP Used 
+the portion of the logical space used by the file and metadata.
+
+.IP Free\ (estimated) 
+the estimated free space available. The evaluation 
+cannot be rigorous because it depends by the allocation policy (DUP,Single,
+RAID1...) of the metadata and data chunks. If every chunks is stored as
+"Single" the sum of the \fBfree (estimated)\fP space and the \fBused\fP 
+space  is equal to the \fBdisk size\fP.
+Otherwise if all the chunk are mirrored (raid1 or raid10) or duplicated
+the sum of the \fBfree (estimated)\fP space and the \fBused\fP space is
+half of the \fBdisk size\fP. Normally the \fBfree (estimated)\fP is between
+these two limits.
+
+.IP Data\ to\ disk\ ratio
+the ratio betwen the \fBlogical size\fP and the \fBdisk allocated\fP.
+
+.IP Mode
+the kind of allocation policy used by the chunk (e.g. DUPlicated,
+RAID1, RAID10, Single....)
+
+.RE
+.RS
+\fINOTE\fP
+
+When a chunk is allocated, its disk-area is used and its allocation
+policy is fixed.
+A rebalance operation could rearrange the chunks, moving data in the chunks
+and resizing the allocated chunks. This causes the change of all the values 
+discussed above, with the exception of the \fBused\fP and 
+\fBdisk size\fP values.
+
+.RE
+.TP
+
 \fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
 Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
 \fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
-- 
1.7.10.4

[PATCH][BTRFS-PROGS][V1] btrfs filesystem df

[Goffredo Baroncelli]

This serie of patches updated the command "btrfs filesystem
df". I update this command because it is not so easy to get
the information about the disk usage from the command "fi df" and "fi show".

>From the man page (see 2nd patch):

[...]
The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
[...]

$ ./btrfs filesystem df --help
usage: btrfs filesystem disk-usage [-d][-s][-k] <path> [<path>..]

    Show space usage information for a mount point(s).

    -k  Set KB (1024 bytes) as unit
    -s  Don't show the summary section
    -d  Don't show the detail section

$ ./btrfs filesystem df /
Path: /
Summary:
  Disk_size:                 72.57GB
  Disk_allocated:            25.10GB
  Disk_unallocated:          47.48GB
  Logical_size:              23.06GB
  Used:                      11.01GB
  Free_(Estimated):          55.66GB    (Max: 59.52GB, Min: 35.78GB)
  Data_to_disk_ratio:           92 %

Details:
  Chunk-type  Mode      Chunk-size Logical-size        Used
  Data        Single       21.01GB      21.01GB     10.34GB
  System      DUP          80.00MB      40.00MB      4.00KB
  System      Single        4.00MB       4.00MB        0.00
  Metadata    DUP           4.00GB       2.00GB    686.93MB
  Metadata    Single        8.00MB       8.00MB        0.00

Where:
        Disk_size                       -> sum of sizes of teh disks
        Disk_allocated                  -> sum of chunk sizes
        Disk_unallocated                -> Disk_size - Disk_allocated
        Logical_size                    -> sum of logical area sizes
        Used                            -> logical area used
        Free_(Estimated)                -> on the basis of allocated
                                           chunk, an estrapolation of
                                           the free space
        Data_to_disk_ratio              -> ration between the space occuped
                                           by a chunk and the real space
                                           available ( due to duplication
                                           and/or RAID level)
        Chunk-type                      -> kind of chunk
        Mode                            -> allocation policy of a chunk
        Chunk-size                      -> area of disk(s) occuped by the
                                           chunk (see it as raw space used)
        Logical-size                    -> logical area size of the chunk
        Used                            -> portion of the logical area
                                           used by the filesystem



You can pull this change from
   http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
branch
   disk_free

Comments are welcome.

BR
Goffredo Baroncelli

Changelog:
V0->V1          Change the name of command from disk-usage to df

Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>

[PATCH 2/2] Update help page

[Goffredo Baroncelli]

---
 man/btrfs.8.in |   94 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 4b0a9f9..ed20448 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -27,6 +27,8 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
 .PP
+\fBbtrfs\fP \fBfilesystem df\fP\fI [-s][-d][-k] \fIpath [path..]\fR\fP
+.PP
 \fBbtrfs\fP \fBsubvolume find-new\fP\fI <subvolume> <last_gen>\fP
 .PP
 \fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
@@ -214,6 +216,98 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
+\fBfilesystem df\fP [-s][-d][-k] \fIpath [path..]\fR
+
+Show space usage information for a mount point.
+
+\fIOptions\fP
+
+\fB-k\fP Set KB (1024 bytes) as unit
+
+\fB-s\fP Don't show the summary section
+
+\fB-d\fP Don't show the detail section
+
+\fIUsage information\fP
+
+.\"
+.\" this section is extract from 
+.\"	http://en.wikipedia.org/wiki/Btrfs#Chunk_and_device_trees
+The disk(s) of a btrfs filesystem are divided into chunks of 256 MB or more. 
+Chunks may be mirrored or striped across multiple devices, depending by
+the allocation policy.
+The mirroring/striping arrangement is transparent to the rest of the 
+file system, which simply sees the single, logical address space that 
+chunks are mapped into.
+Chunks are allocated on demand. In the default allocation policy 
+the data chunks are not duplicated and the metadata chunks
+are duplicated. This default can be changed during the filesystem
+creation, and in general the chunks allocation policy may change
+during the filesystem life. 
+
+A chunk DUPlicated or with a RAID1/RAID10 level 
+requires a space two time greater than the logical one. Different RAID levels
+have a different ratio disk-usage / logical space offered.
+
+Because some files (the small ones) are stored in the 
+metadata chunks the computation of the \fIfree space\fP and \fIused space\fP
+is complex: depending by the file size different allocation policies are used.
+
+The command \fBbtrfs filesystem df\fP is used to query the status
+of the chunks, how many space on the disk(s) are used by the chunks, 
+how many space are available in the chunks, and an estimation of the free
+space of the filesystem.
+The output of the command \fBbtrfs filesystem df\fP shows:
+
+.RS
+.IP Disk\ size 
+the total size of the disks which compose the filesystem.
+
+.IP Disk\ allocated 
+the size of the area of the disks used by the chunks.
+
+.IP Disk\ unallocated 
+the size of the area of the disks which is free (i.e.
+the differences of the values above).
+
+.IP Logical\ size 
+the available logical space of chunk. 
+
+.IP Used 
+the portion of the logical space used by the file and metadata.
+
+.IP Free\ (estimated) 
+the estimated free space available. The evaluation 
+cannot be rigorous because it depends by the allocation policy (DUP,Single,
+RAID1...) of the metadata and data chunks. If every chunks is stored as
+"Single" the sum of the \fBfree (estimated)\fP space and the \fBused\fP 
+space  is equal to the \fBdisk size\fP.
+Otherwise if all the chunk are mirrored (raid1 or raid10) or duplicated
+the sum of the \fBfree (estimated)\fP space and the \fBused\fP space is
+half of the \fBdisk size\fP. Normally the \fBfree (estimated)\fP is between
+these two limits.
+
+.IP Data\ to\ disk\ ratio
+the ratio betwen the \fBlogical size\fP and the \fBdisk allocated\fP.
+
+.IP Mode
+the kind of allocation policy used by the chunk (e.g. DUPlicated,
+RAID1, RAID10, Single....)
+
+.RE
+.RS
+\fINOTE\fP
+
+When a chunk is allocated, its disk-area is used and its allocation
+policy is fixed.
+A rebalance operation could rearrange the chunks, moving data in the chunks
+and resizing the allocated chunks. This causes the change of all the values 
+discussed above, with the exception of the \fBused\fP and 
+\fBdisk size\fP values.
+
+.RE
+.TP
+
 \fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
 Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
 \fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
-- 
1.7.10.4

[PATCH][BTRFS-PROGS] btrfs filesystem disk-usage

[Goffredo Baroncelli]

Hi all,

This serie of patches adds a new command called "btrfs filesystem
disk-usage". I added this command because it is not so easy to get
the information about the disk usage from the command "fi df" and "fi show".

>From the man page (see 2nd patch):

[...]
The  command  btrfs  filesystem  disk-usage is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
[...]

$ ./btrfs filesystem disk-usage --help
usage: btrfs filesystem disk-usage [-d][-s][-k] <path> [<path>..]

    Show space usage information for a mount point(s).

    -k	Set KB (1024 bytes) as unit
    -s	Don't show the summary section
    -d	Don't show the detail section

$ ./btrfs filesystem disk-usage /
Path: /
Summary:
  Disk_size:		     72.57GB
  Disk_allocated:	     25.10GB
  Disk_unallocated:	     47.48GB
  Logical_size:		     23.06GB
  Used:			     11.01GB
  Free_(Estimated):	     55.66GB	(Max: 59.52GB, Min: 35.78GB)
  Data_to_disk_ratio:	        92 %

Details:
  Chunk-type  Mode      Chunk-size Logical-size        Used
  Data        Single       21.01GB      21.01GB     10.34GB
  System      DUP          80.00MB      40.00MB      4.00KB
  System      Single        4.00MB       4.00MB        0.00
  Metadata    DUP           4.00GB       2.00GB    686.93MB
  Metadata    Single        8.00MB       8.00MB        0.00

Where:
	Disk_size			-> sum of sizes of teh disks
	Disk_allocated			-> sum of chunk sizes
	Disk_unallocated		-> Disk_size - Disk_allocated
	Logical_size			-> sum of logical area sizes
	Used				-> logical area used
	Free_(Estimated)		-> on the basis of allocated
					   chunk, an estrapolation of
					   the free space
	Data_to_disk_ratio		-> ration between the space occuped
					   by a chunk and the real space
					   available ( due to duplication
					   and/or RAID level)
	Chunk-type			-> kind of chunk
	Mode				-> allocation policy of a chunk
	Chunk-size			-> area of disk(s) occuped by the
					   chunk (see it as raw space used)
	Logical-size			-> logical area size of the chunk
	Used				-> portion of the logical area
					   used by the filesystem



You can pull this change from 
   http://cassiopea.homelinux.net/git/btrfs-progs-unstable.git
branch
   disk_free

Comments are welcome.

BR
Goffredo Baroncelli

Signed-off-by: Goffredo Baroncelli <kreijack@inwind.it>
	

[PATCH 2/2] Update help page

[Goffredo Baroncelli]

From: Goffredo Baroncelli <kreijack@inwind.it>

---
 man/btrfs.8.in |   94 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)

diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 4b0a9f9..3215216 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -27,6 +27,8 @@ btrfs \- control a btrfs filesystem
 .PP
 \fBbtrfs\fP \fBfilesystem label\fP\fI <dev> [newlabel]\fP
 .PP
+\fBbtrfs\fP \fBfilesystem disk-usage\fP\fI [-s][-d][-k] \fIpath [path..]\fR\fP
+.PP
 \fBbtrfs\fP \fBsubvolume find-new\fP\fI <subvolume> <last_gen>\fP
 .PP
 \fBbtrfs\fP \fBfilesystem balance\fP\fI <path> \fP
@@ -214,6 +216,98 @@ NOTE: Currently there are the following limitations:
 - the filesystem should not have more than one device.
 .TP
 
+\fBfilesystem disk-usage\fP [-s][-d][-k] \fIpath [path..]\fR
+
+Show space usage information for a mount point.
+
+\fIOptions\fP
+
+\fB-k\fP Set KB (1024 bytes) as unit
+
+\fB-s\fP Don't show the summary section
+
+\fB-d\fP Don't show the detail section
+
+\fIUsage information\fP
+
+.\"
+.\" this section is extract from 
+.\"	http://en.wikipedia.org/wiki/Btrfs#Chunk_and_device_trees
+The disk(s) of a btrfs filesystem are divided into chunks of 256 MB or more. 
+Chunks may be mirrored or striped across multiple devices, depending by
+the allocation policy.
+The mirroring/striping arrangement is transparent to the rest of the 
+file system, which simply sees the single, logical address space that 
+chunks are mapped into.
+Chunks are allocated on demand. In the default allocation policy 
+the data chunks are not duplicated and the metadata chunks
+are duplicated. This default can be changed during the filesystem
+creation, and in general the chunks allocation policy may change
+during the filesystem life. 
+
+A chunk DUPlicated or with a RAID1/RAID10 level 
+requires a space two time greater than the logical one. Different RAID levels
+have a different ratio disk-usage / logical space offered.
+
+Because some files (the small ones) are stored in the 
+metadata chunks the computation of the \fIfree space\fP and \fIused space\fP
+is complex: depending by the file size different allocation policies are used.
+
+The command \fBbtrfs filesystem disk-usage\fP is used to query the status
+of the chunks, how many space on the disk(s) are used by the chunks, 
+how many space are available in the chunks, and an estimation of the free
+space of the filesystem.
+The output of the command \fBbtrfs filesystem disk-usage\fP shows:
+
+.RS
+.IP Disk\ size 
+the total size of the disks which compose the filesystem.
+
+.IP Disk\ allocated 
+the size of the area of the disks used by the chunks.
+
+.IP Disk\ unallocated 
+the size of the area of the disks which is free (i.e.
+the differences of the values above).
+
+.IP Logical\ size 
+the available logical space of chunk. 
+
+.IP Used 
+the portion of the logical space used by the file and metadata.
+
+.IP Free\ (estimated) 
+the estimated free space available. The evaluation 
+cannot be rigorous because it depends by the allocation policy (DUP,Single,
+RAID1...) of the metadata and data chunks. If every chunks is stored as
+"Single" the sum of the \fBfree (estimated)\fP space and the \fBused\fP 
+space  is equal to the \fBdisk size\fP.
+Otherwise if all the chunk are mirrored (raid1 or raid10) or duplicated
+the sum of the \fBfree (estimated)\fP space and the \fBused\fP space is
+half of the \fBdisk size\fP. Normally the \fBfree (estimated)\fP is between
+these two limits.
+
+.IP Data\ to\ disk\ ratio
+the ratio betwen the \fBlogical size\fP and the \fBdisk allocated\fP.
+
+.IP Mode
+the kind of allocation policy used by the chunk (e.g. DUPlicated,
+RAID1, RAID10, Single....)
+
+.RE
+.RS
+\fINOTE\fP
+
+When a chunk is allocated, its disk-area is used and its allocation
+policy is fixed.
+A rebalance operation could rearrange the chunks, moving data in the chunks
+and resizing the allocated chunks. This causes the change of all the values 
+discussed above, with the exception of the \fBused\fP and 
+\fBdisk size\fP values.
+
+.RE
+.TP
+
 \fBfilesystem show\fR [--all-devices|<uuid>|<label>]\fR
 Show the btrfs filesystem with some additional info. If no \fIUUID\fP or 
 \fIlabel\fP is passed, \fBbtrfs\fR show info of all the btrfs filesystem.
-- 
1.7.10.4