On 2011-01-23, at 20:46, Robin Dong wrote:
> Having a view of blocks usage of block group descriptors, block/inode bitmaps, inode table, block pointer blocks, extents .etc, can help users in many cases,
> 1) Make estimation on how many memory might be occupied as buffer cache or page cache.
> 2) For some specific workload, is a file system is well formatted for block usage, e.g. whether there are never-be-used blocks allocated for inode table.
> 3) If there is a chance to allocated meta data from non-seek-cost device like SSD as a meta-data device, first of all user should know how many meta data blocks are allocated/used on the file system.
>
> Therefore a tool to collect block usage information and display in a clear view is necessary. This patch is a first effort to provide such a tool which is called e2view so far.
Much of this information is available via "dumpe2fs -h" already, though perhaps a more clear summary of the total block usage could be added to dumpe2fs.
Instead, perhaps a better summary for the e2freefrag tool would be good, which also prints out a histogram of free blocks in the filesystem.
I'd personally rather avoid adding another tool to print information like this, and just make one of the existing tools print it.
> [Example]
> An example of e2view execution looks like this:
>
> #e2view /dev/mapper/sys-var
>
> result:
> e2view 1.41.14 (22-Dec-2010)
> Super block: 9 Block
> Group descriptor: 9 Block
> Reserved GDT: 4600 Block
> Inode table: 65536 Block
> Inode bitmap: 9 Block
> Block bitmap: 9 Block
> Link block: 0 Block
> Journal: 32802 Block
> Directory: 644 Block
> Extent: 0 Block
> Ind-Block: 574 Block
> Dind-Block: 172 Block
> Tind-Block: 0 Block
> File Data: 309069 Block
> ACL block: 194 Block
>
>
> Signed-off-by: Robin Dong <sanbai@xxxxxxxxxx>
> ---
> misc/Makefile.in | 19 ++-
> misc/e2view.c | 482 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 498 insertions(+), 3 deletions(-)
> create mode 100644 misc/e2view.c
>
> diff --git a/misc/Makefile.in b/misc/Makefile.in
> index 86ee53f..32b7c93 100644
> --- a/misc/Makefile.in
> +++ b/misc/Makefile.in
> @@ -17,6 +17,8 @@ INSTALL = @INSTALL@
> @IMAGER_CMT@E2IMAGE_PROG= e2image
> @IMAGER_CMT@E2IMAGE_MAN= e2image.8
>
> +@IMAGER_CMT@E2IMAGE_PROG= e2view
> +
> @UUIDD_CMT@UUIDD_PROG= uuidd
> @UUIDD_CMT@UUIDD_MAN= uuidd.8
>
> @@ -50,6 +52,7 @@ UUIDD_OBJS= uuidd.o
> DUMPE2FS_OBJS= dumpe2fs.o
> BADBLOCKS_OBJS= badblocks.o
> E2IMAGE_OBJS= e2image.o
> +E2VIEW_OBJS= e2view.o
> FSCK_OBJS= fsck.o base_device.o ismounted.o
> BLKID_OBJS= blkid.o
> FILEFRAG_OBJS= filefrag.o
> @@ -68,6 +71,7 @@ PROFILED_UUIDD_OBJS= profiled/uuidd.o
> PROFILED_DUMPE2FS_OBJS= profiled/dumpe2fs.o
> PROFILED_BADBLOCKS_OBJS= profiled/badblocks.o
> PROFILED_E2IMAGE_OBJS= profiled/e2image.o
> +PROFILED_E2VIEW_OBJS= profiled/e2view.o
> PROFILED_FSCK_OBJS= profiled/fsck.o profiled/base_device.o \
> profiled/ismounted.o
> PROFILED_BLKID_OBJS= profiled/blkid.o
> @@ -106,7 +110,7 @@ COMPILE_ET=$(top_builddir)/lib/et/compile_et --build-tree
> all:: profiled $(SPROGS) $(UPROGS) $(USPROGS) $(SMANPAGES) $(UMANPAGES) \
> $(FMANPAGES) $(LPROGS) $(E4DEFRAG_PROG)
>
> -@PROFILE_CMT@all:: tune2fs.profiled blkid.profiled e2image.profiled \
> +@PROFILE_CMT@all:: tune2fs.profiled blkid.profiled e2image.profiled e2view.profiled \
> e2undo.profiled mke2fs.profiled dumpe2fs.profiled fsck.profiled \
> logsave.profiled filefrag.profiled uuidgen.profiled uuidd.profiled \
> e2image.profiled e4defrag.profiled
> @@ -187,6 +191,15 @@ e2image.profiled: $(PROFILED_E2IMAGE_OBJS) $(PROFILED_DEPLIBS)
> $(Q) $(CC) $(ALL_LDFLAGS) -g -pg -o e2image.profiled \
> $(PROFILED_E2IMAGE_OBJS) $(PROFILED_LIBS) $(LIBINTL)
>
> +e2view: $(E2VIEW_OBJS) $(DEPLIBS)
> + $(E) " LD $@"
> + $(Q) $(CC) $(ALL_LDFLAGS) -o e2view $(E2VIEW_OBJS) $(LIBS) $(LIBINTL)
> +
> +e2view.profiled: $(PROFILED_E2VIEW_OBJS) $(PROFILED_DEPLIBS)
> + $(E) " LD $@"
> + $(Q) $(CC) $(ALL_LDFLAGS) -g -pg -o e2view.profiled \
> + $(PROFILED_E2VIEW_OBJS) $(PROFILED_LIBS) $(LIBINTL)
> +
> e2undo: $(E2UNDO_OBJS) $(DEPLIBS)
> $(E) " LD $@"
> $(Q) $(CC) $(ALL_LDFLAGS) -o e2undo $(E2UNDO_OBJS) $(LIBS) $(LIBINTL)
> @@ -550,8 +563,8 @@ clean:
> $(FMANPAGES) \
> base_device base_device.out mke2fs.static filefrag e2freefrag \
> e2initrd_helper partinfo prof_err.[ch] default_profile.c \
> - uuidd e2image tune2fs.static tst_ismounted fsck.profiled \
> - blkid.profiled tune2fs.profiled e2image.profiled \
> + uuidd e2image e2view tune2fs.static tst_ismounted fsck.profiled \
> + blkid.profiled tune2fs.profiled e2image.profiled e2view.profiled\
> e2undo.profiled mke2fs.profiled dumpe2fs.profiled \
> logsave.profiled filefrag.profiled uuidgen.profiled \
> uuidd.profiled e2image.profiled \
> diff --git a/misc/e2view.c b/misc/e2view.c
> new file mode 100644
> index 0000000..679bbb8
> --- /dev/null
> +++ b/misc/e2view.c
> @@ -0,0 +1,482 @@
> +/*
> + * e2view.c --- provide a view of block usage of a specific file system
> + *
> + * Some code borrowed from misc/e2image.c and is:
> + *
> + * Copyright 2000, 2001 by Theodore Ts'o.
> + *
> + * The rest is Copyright (C) 2011 Taobao, all rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public
> + * License, version 2, as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + *
> + * Authors: Robin Dong <sanbai@xxxxxxxxxx>
> + */
> +
> +#define _LARGEFILE_SOURCE
> +#define _LARGEFILE64_SOURCE
> +
> +#include <fcntl.h>
> +#include <grp.h>
> +#ifdef HAVE_GETOPT_H
> +#include <getopt.h>
> +#else
> +extern char *optarg;
> +extern int optind;
> +#endif
> +#include <pwd.h>
> +#include <stdio.h>
> +#ifdef HAVE_STDLIB_H
> +#include <stdlib.h>
> +#endif
> +#include <string.h>
> +#include <time.h>
> +#include <unistd.h>
> +#include <fcntl.h>
> +#include <errno.h>
> +#include <sys/stat.h>
> +#include <sys/types.h>
> +
> +#include "ext2fs/ext2_fs.h"
> +#include "ext2fs/ext2fs.h"
> +#include "et/com_err.h"
> +#include "uuid/uuid.h"
> +#include "e2p/e2p.h"
> +
> +#include "../version.h"
> +#include "nls-enable.h"
> +
> +#define SECTOR_SIZE 512
> +#define UNIT_SIZE 64
> +
> +const char * program_name = "e2view";
> +char * device_name = NULL;
> +
> +static void usage(void)
> +{
> + fprintf(stderr, _("Usage: [-dkm] %s <filesystem>\n"),
> + program_name);
> + exit (1);
> +}
> +
> +struct fs_meta_count {
> + unsigned long super_block_counts;
> + unsigned long group_desc_counts;
> + unsigned long reserved_gdt_counts;
> + unsigned long inode_table_counts;
> + unsigned long inode_bitmap_counts;
> + unsigned long block_bitmap_counts;
> + unsigned long dir_block;
> + unsigned long acl_block;
> + unsigned long file_data_block;
> + unsigned long file_data_extent_block;
> + unsigned long file_data_ind_block;
> + unsigned long file_data_dind_block;
> + unsigned long file_data_tind_block;
> + unsigned long link_block;
> + unsigned long journal_block;
> +};
> +
> +struct fs_meta_count meta_counter;
> +
> +struct process_block_struct {
> + ext2_ino_t ino;
> + int is_dir;
> + __u32 i_flags;
> +};
> +
> +/*
> + * These subroutines short circuits ext2fs_get_blocks and
> + * ext2fs_check_directory; we use them since we already have the inode
> + * structure, so there's no point in letting the ext2fs library read
> + * the inode again.
> + */
> +static ino_t stashed_ino = 0;
> +static struct ext2_inode *stashed_inode;
> +
> +static errcode_t meta_get_blocks(ext2_filsys fs EXT2FS_ATTR((unused)),
> + ext2_ino_t ino,
> + blk_t *blocks)
> +{
> + int i;
> +
> + if ((ino != stashed_ino) || !stashed_inode)
> + return EXT2_ET_CALLBACK_NOTHANDLED;
> +
> + for (i=0; i < EXT2_N_BLOCKS; i++)
> + blocks[i] = stashed_inode->i_block[i];
> + return 0;
> +}
> +
> +static errcode_t meta_check_directory(ext2_filsys fs EXT2FS_ATTR((unused)),
> + ext2_ino_t ino)
> +{
> + if ((ino != stashed_ino) || !stashed_inode)
> + return EXT2_ET_CALLBACK_NOTHANDLED;
> +
> + if (!LINUX_S_ISDIR(stashed_inode->i_mode))
> + return EXT2_ET_NO_DIRECTORY;
> + return 0;
> +}
> +
> +static errcode_t meta_read_inode(ext2_filsys fs EXT2FS_ATTR((unused)),
> + ext2_ino_t ino,
> + struct ext2_inode *inode)
> +{
> + if ((ino != stashed_ino) || !stashed_inode)
> + return EXT2_ET_CALLBACK_NOTHANDLED;
> + *inode = *stashed_inode;
> + return 0;
> +}
> +
> +static void use_inode_shortcuts(ext2_filsys fs, int bool)
> +{
> + if (bool) {
> + fs->get_blocks = meta_get_blocks;
> + fs->check_directory = meta_check_directory;
> + fs->read_inode = meta_read_inode;
> + stashed_ino = 0;
> + } else {
> + fs->get_blocks = 0;
> + fs->check_directory = 0;
> + fs->read_inode = 0;
> + }
> +}
> +
> +static int process_journal_block(ext2_filsys fs EXT2FS_ATTR((unused)),
> + blk64_t *block_nr,
> + e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
> + blk64_t ref_block EXT2FS_ATTR((unused)),
> + int ref_offset EXT2FS_ATTR((unused)),
> + void *priv_data EXT2FS_ATTR((unused)))
> +{
> + meta_counter.journal_block ++;
> + return 0;
> +}
> +
> +static int process_dir_block(ext2_filsys fs EXT2FS_ATTR((unused)),
> + blk64_t *block_nr,
> + e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
> + blk64_t ref_block EXT2FS_ATTR((unused)),
> + int ref_offset EXT2FS_ATTR((unused)),
> + void *priv_data EXT2FS_ATTR((unused)))
> +{
> + meta_counter.dir_block ++;
> + return 0;
> +}
> +
> +static int process_file_block(ext2_filsys fs EXT2FS_ATTR((unused)),
> + blk64_t *block_nr,
> + e2_blkcnt_t blockcnt,
> + blk64_t ref_block EXT2FS_ATTR((unused)),
> + int ref_offset EXT2FS_ATTR((unused)),
> + void *priv_data EXT2FS_ATTR((unused)))
> +{
> + struct process_block_struct *p;
> +
> + p = (struct process_block_struct *) priv_data;
> +
> + if (p->i_flags & EXT4_EXTENTS_FL) {
> + /*
> + * leaf node block
> + */
> + if (blockcnt == -1) {
> + meta_counter.file_data_extent_block ++;
> + }
> + } else {
> + if (blockcnt == BLOCK_COUNT_IND) {
> + meta_counter.file_data_ind_block ++;
> + } else if (blockcnt == BLOCK_COUNT_DIND) {
> + meta_counter.file_data_dind_block ++;
> + } else if (blockcnt == BLOCK_COUNT_TIND) {
> + meta_counter.file_data_tind_block ++;
> + }
> + }
> +
> + meta_counter.file_data_block ++;
> +
> + return 0;
> +}
> +
> +static void calculate_table_blocks(ext2_filsys fs, int debug_flag)
> +{
> + blk64_t first_block, b;
> + unsigned int i,j;
> +
> + first_block = fs->super->s_first_data_block;
> +
> + /*
> + * calculate the block_bitmap/inode_bitmap/inode_table
> + */
> + meta_counter.block_bitmap_counts = fs->group_desc_count;
> + meta_counter.inode_bitmap_counts = fs->group_desc_count;
> + meta_counter.inode_table_counts =
> + fs->inode_blocks_per_group * fs->group_desc_count;
> +
> + for (i = 0; i < fs->group_desc_count; i++) {
> + if (i == 0) {
> + meta_counter.reserved_gdt_counts += 1;
> + }
> +
> + if (ext2fs_bg_has_super(fs, i)) {
> + meta_counter.super_block_counts += 1;
> + meta_counter.group_desc_counts += fs->desc_blocks;
> + meta_counter.reserved_gdt_counts +=
> + fs->super->s_reserved_gdt_blocks;
> + if (debug_flag) {
> + printf("group%ld has suer block. gdt:%ld\n", i,
> + fs->super->s_reserved_gdt_blocks);
> + }
> + }
> + }
> +}
> +
> +int name_id[256];
> +
> +#define EXT4_MAX_REC_LEN ((1<<16)-1)
> +
> +static void calculate_metadata(ext2_filsys fs, int fd, int debug_flag)
> +{
> + struct process_block_struct pb;
> + struct ext2_inode inode;
> + ext2_inode_scan scan;
> + ext2_ino_t ino;
> + errcode_t retval;
> + char * block_buf;
> +
> + calculate_table_blocks(fs, debug_flag);
> +
> + retval = ext2fs_open_inode_scan(fs, 0, &scan);
> + if (retval) {
> + com_err(program_name, retval, _("while opening inode scan"));
> + exit(1);
> + }
> +
> + block_buf = malloc(fs->blocksize * 3);
> + if (!block_buf) {
> + com_err(program_name, 0, "Can't allocate block buffer");
> + exit(1);
> + }
> +
> + use_inode_shortcuts(fs, 1);
> + stashed_inode = &inode;
> + while (1) {
> + retval = ext2fs_get_next_inode(scan, &ino, &inode);
> + if (retval == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE)
> + continue;
> + if (retval) {
> + com_err(program_name, retval,
> + _("while getting next inode"));
> + exit(1);
> + }
> + if (ino == 0)
> + break;
> + if (!inode.i_links_count)
> + continue;
> + if (ext2fs_file_acl_block(&inode)) {
> + meta_counter.acl_block++;
> + }
> + if (!ext2fs_inode_has_valid_blocks(&inode))
> + continue;
> +
> + stashed_ino = ino;
> + pb.ino = ino;
> + pb.is_dir = LINUX_S_ISDIR(inode.i_mode);
> + pb.i_flags = inode.i_flags;
> + /* calc journal block */
> + if (ino == fs->super->s_journal_inum) {
> + retval = ext2fs_block_iterate3(fs, ino,
> + BLOCK_FLAG_READ_ONLY, block_buf,
> + process_journal_block, &pb);
> + if (retval) {
> + com_err(program_name, retval,
> + "while iterating over journal inode %u",
> + ino);
> + exit(1);
> + }
> + } else if (LINUX_S_ISDIR(inode.i_mode)) {
> + retval = ext2fs_block_iterate3(fs, ino,
> + BLOCK_FLAG_READ_ONLY, block_buf,
> + process_dir_block, &pb);
> + if (retval) {
> + com_err(program_name, retval,
> + "while iterating over inode %u",
> + ino);
> + exit(1);
> + }
> + } else if (LINUX_S_ISLNK(inode.i_mode) &&
> + ext2fs_inode_has_valid_blocks(&inode)) {
> + if (debug_flag) {
> + printf("ino:%lu link i_blocks:%lu\n", ino,
> + inode.i_blocks);
> + }
> + meta_counter.link_block += inode.i_blocks *
> + SECTOR_SIZE / fs->blocksize;
> + } else {
> + if ((inode.i_flags & EXT4_EXTENTS_FL) ||
> + inode.i_block[EXT2_IND_BLOCK] ||
> + inode.i_block[EXT2_DIND_BLOCK] ||
> + inode.i_block[EXT2_TIND_BLOCK])
> + {
> + if (debug_flag) {
> + printf("ino:%lu inode i_blocks:%lu\n", ino,
> + inode.i_blocks);
> + }
> + retval = ext2fs_block_iterate3(fs,
> + ino, BLOCK_FLAG_READ_ONLY, block_buf,
> + process_file_block, &pb);
> + if (retval) {
> + com_err(program_name, retval,
> + "while iterating over inode %u", ino);
> + exit(1);
> + }
> + } else {
> + if (debug_flag) {
> + printf("ino:%lu normal inode i_blocks:%lu\n", ino,
> + inode.i_blocks);
> + }
> + meta_counter.file_data_block += inode.i_blocks *
> + SECTOR_SIZE / fs->blocksize;
> + }
> + }
> + }
> + use_inode_shortcuts(fs, 0);
> + free(block_buf);
> +}
> +
> +void change_unit(ext2_filsys fs,
> + struct fs_meta_count *counter,
> + unsigned long unit)
> +{
> + int i;
> + int nr = sizeof(struct fs_meta_count) / sizeof(unsigned long);
> + unsigned long *p = (unsigned long*)counter;
> +
> + for (i=0; i < nr; i++)
> + *(p + i) = *(p + i) * fs->blocksize / unit;
> +}
> +
> +int main (int argc, char ** argv)
> +{
> + int c;
> + errcode_t retval;
> + ext2_filsys fs;
> + char *image_fn;
> + char unit[UNIT_SIZE];
> + int open_flag = EXT2_FLAG_64BITS;
> + int debug_flag = 0;
> + int kilobytes_flag = 0;
> + int megabytes_flag = 0;
> + int fd = 0;
> +
> +#ifdef ENABLE_NLS
> + setlocale(LC_MESSAGES, "");
> + setlocale(LC_CTYPE, "");
> + bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
> + textdomain(NLS_CAT_NAME);
> +#endif
> + fprintf (stderr, "e2view %s (%s)\n", E2FSPROGS_VERSION,
> + E2FSPROGS_DATE);
> + if (argc && *argv)
> + program_name = *argv;
> + add_error_table(&et_ext2_error_table);
> + while ((c = getopt (argc, argv, "dkm")) != EOF)
> + switch (c) {
> + case 'd':
> + debug_flag++;
> + break;
> + case 'k':
> + kilobytes_flag++;
> + break;
> + case 'm':
> + megabytes_flag++;
> + break;
> + default:
> + usage();
> + }
> + if (optind != argc - 1 ||
> + (kilobytes_flag && megabytes_flag))
> + usage();
> +
> + device_name = argv[optind];
> +
> + retval = ext2fs_open (device_name, open_flag, 0, 0,
> + unix_io_manager, &fs);
> + if (retval) {
> + com_err (program_name, retval, _("while trying to open %s"),
> + device_name);
> + fputs(_("Couldn't find valid filesystem superblock.\n"), stdout);
> + exit(1);
> + }
> +
> + memset(&meta_counter, 0, sizeof(struct fs_meta_count));
> +
> + calculate_metadata(fs, fd, debug_flag);
> +
> + /*
> + * take off the blocks of Reserved_GDT
> + */
> + meta_counter.file_data_ind_block -=
> + fs->super->s_reserved_gdt_blocks;
> + meta_counter.file_data_dind_block -= 1;
> + meta_counter.file_data_block -= meta_counter.reserved_gdt_counts;
> +
> + /*
> + * take off the xattr block (ACL block)
> + */
> + meta_counter.file_data_block -= meta_counter.acl_block;
> +
> + /*
> + * display the different units
> + */
> + if (kilobytes_flag) {
> + change_unit(fs, &meta_counter, 1024);
> + sprintf(unit, " %s", "KB");
> + } else if (megabytes_flag) {
> + change_unit(fs, &meta_counter, 1024*1024);
> + sprintf(unit, " %s", "MB");
> + } else {
> + sprintf(unit, " %s", "Block");
> + }
> +
> + printf("Super block: %8lu%s\n",
> + meta_counter.super_block_counts, unit);
> + printf("Group descriptor:%8lu%s\n",
> + meta_counter.group_desc_counts, unit);
> + printf("Reserved GDT: %8lu%s\n",
> + meta_counter.reserved_gdt_counts, unit);
> + printf("Inode table: %8lu%s\n",
> + meta_counter.inode_table_counts, unit);
> + printf("Inode bitmap: %8lu%s\n",
> + meta_counter.inode_bitmap_counts, unit);
> + printf("Block bitmap: %8lu%s\n",
> + meta_counter.block_bitmap_counts, unit);
> + printf("Link block: %8lu%s\n",
> + meta_counter.link_block, unit);
> + printf("Journal: %8lu%s\n",
> + meta_counter.journal_block, unit);
> + printf("Directory: %8lu%s\n",
> + meta_counter.dir_block, unit);
> + printf("Extent: %8lu%s\n",
> + meta_counter.file_data_extent_block, unit);
> + printf("Ind-Block: %8lu%s\n",
> + meta_counter.file_data_ind_block, unit);
> + printf("Dind-Block: %8lu%s\n",
> + meta_counter.file_data_dind_block, unit);
> + printf("Tind-Block: %8lu%s\n",
> + meta_counter.file_data_tind_block, unit);
> + printf("File Data: %8lu%s\n",
> + meta_counter.file_data_block, unit);
> + printf("ACL block: %8lu%s\n",
> + meta_counter.acl_block, unit);
> +
> + ext2fs_close (fs);
> + remove_error_table(&et_ext2_error_table);
> + exit (0);
> +}
> --
> 1.7.3.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
Cheers, Andreas
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
