2011-06-15 06:42:18

by Kazuya Mio

[permalink] [raw]
Subject: [PATCH 02/11 RESEND] filefrag: Output fragmentation score

This patch adds the fragmentation score to the output of filefrag.
The threshold that shows whether a fragment is good or not comes from
"blocksize * 8 - 2048". "blocksize * 8 - 2048" is the maximum number of
contiguous blocks which we can get from empty blockgroup containing some
metadata blocks.

For example, filefrag shows fragmentation score as follows:

# filefrag /mnt/mp1/testfile
/mnt/mp1/testfile: 4 extents found
Fragmentation score: 33 (found a little bit fragmentation)

Signed-off-by: Kazuya Mio <[email protected]>
---
misc/Makefile.in | 4 ++--
misc/filefrag.c | 28 ++++++++++++++++++++++++++++
2 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/misc/Makefile.in b/misc/Makefile.in
index 86ee53f..19eaa43 100644
--- a/misc/Makefile.in
+++ b/misc/Makefile.in
@@ -306,9 +306,9 @@ e2freefrag: $(E2FREEFRAG_OBJS)
$(E) " LD $@"
$(Q) $(CC) $(ALL_LDFLAGS) -o e2freefrag $(E2FREEFRAG_OBJS) $(LIBS)

-filefrag: $(FILEFRAG_OBJS)
+filefrag: $(FILEFRAG_OBJS) $(DEPLIBS_E2P)
$(E) " LD $@"
- $(Q) $(CC) $(ALL_LDFLAGS) -o filefrag $(FILEFRAG_OBJS)
+ $(Q) $(CC) $(ALL_LDFLAGS) -o filefrag $(FILEFRAG_OBJS) $(DEPLIBS_E2P)

filefrag.profiled: $(PROFILED_FILEFRAG_OBJS)
$(E) " LD $@"
diff --git a/misc/filefrag.c b/misc/filefrag.c
index 2795e15..ca9833a 100644
--- a/misc/filefrag.c
+++ b/misc/filefrag.c
@@ -41,6 +41,7 @@ extern int optind;
#include <linux/fd.h>
#include <ext2fs/ext2_types.h>
#include <ext2fs/fiemap.h>
+#include "e2p/e2p.h"

int verbose = 0;
int no_bs = 0; /* Don't use the files blocksize, use 1K blocksize */
@@ -279,6 +280,7 @@ static void frag_report(const char *filename)
int is_ext2 = 0;
static int once = 1;
unsigned int flags;
+ int score;
int rc;

#ifdef HAVE_OPEN64
@@ -379,6 +381,32 @@ static void frag_report(const char *filename)
(expected>1) ? "s" : "");
else
fputc('\n', stdout);
+
+ if (!xattr_map) {
+ /*
+ * Get the fragmentation score.
+ * NOTE: 2048 means the maximum block region of mballoc.
+ */
+ score = get_fragment_score(fd,
+ (fsinfo.f_bsize * 8 - 2048) * fsinfo.f_bsize);
+
+ /*
+ * Print fragmentation score with some comments
+ * 0-30 no problem, 31-55 a little bit fragmented,
+ * 56- needs defrag
+ */
+ if (score < 0)
+ ;
+ else if (score <= 30)
+ printf("Fragmentation score: %d (no problem)\n", score);
+ else if (score <= 55)
+ printf("Fragmentation score: %d "
+ "(found a little bit fragmentation)\n", score);
+ else
+ printf("Fragmentation score: %d "
+ "(need to do e4defrag command)\n", score);
+ }
+
close(fd);
once = 0;
}



2011-06-16 03:12:24

by Andreas Dilger

[permalink] [raw]
Subject: Re: [PATCH 02/11 RESEND] filefrag: Output fragmentation score

On 2011-06-15, at 12:33 AM, Kazuya Mio <[email protected]> wrote:
> This patch adds the fragmentation score to the output of filefrag.
> The threshold that shows whether a fragment is good or not comes from
> "blocksize * 8 - 2048". "blocksize * 8 - 2048" is the maximum number of
> contiguous blocks which we can get from empty blockgroup containing some
> metadata blocks.
>
> For example, filefrag shows fragmentation score as follows:
>
> # filefrag /mnt/mp1/testfile
> /mnt/mp1/testfile: 4 extents found
> Fragmentation score: 33 (found a little bit fragmentation)

It would probably be just as clear, and a lot more compact to keep only a single line per file:

# filefrag /mnt/mp1/testfile
/mnt/mp1/testfile: 4 extents found, 33% fragmented

or similar like "..., fragmentation score 33/100" if we don't like to use percent.

> Signed-off-by: Kazuya Mio <[email protected]>
> ---
> misc/Makefile.in | 4 ++--
> misc/filefrag.c | 28 ++++++++++++++++++++++++++++
> 2 files changed, 30 insertions(+), 2 deletions(-)
> diff --git a/misc/Makefile.in b/misc/Makefile.in
> index 86ee53f..19eaa43 100644
> --- a/misc/Makefile.in
> +++ b/misc/Makefile.in
> @@ -306,9 +306,9 @@ e2freefrag: $(E2FREEFRAG_OBJS)
> $(E) " LD $@"
> $(Q) $(CC) $(ALL_LDFLAGS) -o e2freefrag $(E2FREEFRAG_OBJS) $(LIBS)
>
> -filefrag: $(FILEFRAG_OBJS)
> +filefrag: $(FILEFRAG_OBJS) $(DEPLIBS_E2P)
> $(E) " LD $@"
> - $(Q) $(CC) $(ALL_LDFLAGS) -o filefrag $(FILEFRAG_OBJS)
> + $(Q) $(CC) $(ALL_LDFLAGS) -o filefrag $(FILEFRAG_OBJS) $(DEPLIBS_E2P)
>
> filefrag.profiled: $(PROFILED_FILEFRAG_OBJS)
> $(E) " LD $@"
> diff --git a/misc/filefrag.c b/misc/filefrag.c
> index 2795e15..ca9833a 100644
> --- a/misc/filefrag.c
> +++ b/misc/filefrag.c
> @@ -41,6 +41,7 @@ extern int optind;
> #include <linux/fd.h>
> #include <ext2fs/ext2_types.h>
> #include <ext2fs/fiemap.h>
> +#include "e2p/e2p.h"
>
> int verbose = 0;
> int no_bs = 0; /* Don't use the files blocksize, use 1K blocksize */
> @@ -279,6 +280,7 @@ static void frag_report(const char *filename)
> int is_ext2 = 0;
> static int once = 1;
> unsigned int flags;
> + int score;
> int rc;
>
> #ifdef HAVE_OPEN64
> @@ -379,6 +381,32 @@ static void frag_report(const char *filename)
> (expected>1) ? "s" : "");
> else
> fputc('\n', stdout);
> +
> + if (!xattr_map) {
> + /*
> + * Get the fragmentation score.
> + * NOTE: 2048 means the maximum block region of mballoc.
> + */
> + score = get_fragment_score(fd,
> + (fsinfo.f_bsize * 8 - 2048) * fsinfo.f_bsize);
> +
> + /*
> + * Print fragmentation score with some comments
> + * 0-30 no problem, 31-55 a little bit fragmented,
> + * 56- needs defrag
> + */
> + if (score < 0)
> + ;
> + else if (score <= 30)
> + printf("Fragmentation score: %d (no problem)\n", score);
> + else if (score <= 55)
> + printf("Fragmentation score: %d "
> + "(found a little bit fragmentation)\n", score);
> + else
> + printf("Fragmentation score: %d "
> + "(need to do e4defrag command)\n", score);
> + }
> +
> close(fd);
> once = 0;
> }
>
> --
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