tier/ctr: Providing option to record or ignore metadata heat

Currently we heat up a file for both data and metadata write.
Here we provide a ctr xlator option called "ctr-record-metadata-heat"
were the admin can decide on recording metadata heat i.e heatup a
file on metadata writes or not.
Metadata data operation are
a. setattr: explicit changing of atime/mtime using utimes,
            changing of posix permissions of the file
b. rename: Renaming a file,
c. unlink, link: adding or deleting hardlinks
d. xattrs: setting or removal of xattrs.

NOTE: atime, mtime and ctime change through writev, readv, truncate, mknod
and create will not be considered here as these fops are data and primary
metadata fops.

Defaultly "ctr-record-metadata-heat" is off. Admin can
switch it on using gluster volume set command.

Backport of http://review.gluster.org/12540

> Change-Id: I91157509255dd5cb429cda2b6d4f64582e155e7b
> BUG: 1279166
> Signed-off-by: Joseph Fernandes <josferna@redhat.com>
> Reviewed-on: http://review.gluster.org/12540
> Tested-by: NetBSD Build System <jenkins@build.gluster.org>
> Tested-by: Gluster Build System <jenkins@build.gluster.com>
> Reviewed-by: Dan Lambright <dlambrig@redhat.com>
> Tested-by: Dan Lambright <dlambrig@redhat.com>
Signed-off-by: Joseph Fernandes <josferna@redhat.com>

Change-Id: I986c319f0cc337b0692a1dd02f71254e786afac4
BUG: 1282315
Reviewed-on: http://review.gluster.org/12582
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Tested-by: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Dan Lambright <dlambrig@redhat.com>
Tested-by: Dan Lambright <dlambrig@redhat.com>

1 files changed, 21 insertions, 3 deletions

diff --git a/libglusterfs/src/gfdb/gfdb_sqlite3_helper.c b/libglusterfs/src/gfdb/gfdb_sqlite3_helper.c
index cc9658be38c..fde2909b575 100644
--- a/libglusterfs/src/gfdb/gfdb_sqlite3_helper.c
+++ b/libglusterfs/src/gfdb/gfdb_sqlite3_helper.c
@@ -807,15 +807,33 @@ gf_sql_insert_wind (gf_sql_connection_t  *sql_conn,
                                         gfdb_db_record->file_name,
                                         gfdb_db_record->file_path,
                                         gfdb_db_record->link_consistency,
-                                        gfdb_db_record->ignore_errors);
+                                        _gf_true);
                         if (ret) {
                                 gf_msg (GFDB_STR_SQLITE3,
-                                        _gfdb_log_level (GF_LOG_ERROR,
+                                        _gfdb_log_level (GF_LOG_WARNING,
                                                 gfdb_db_record->ignore_errors),
                                         0,
                                         LG_MSG_INSERT_FAILED, "Failed "
                                         "inserting link in DB");
-                                goto out;
+                                /* Even if link creation is failed we
+                                 * continue with the creation of file record.
+                                 * This covers to cases
+                                 * 1) Lookup heal: If the file record from
+                                 * gf_file_tb is deleted but the link record
+                                 * still exist. Lookup heal will attempt a heal
+                                 * with create_wind set. The link heal will fail
+                                 * as there is already a record and if we dont
+                                 * ignore the error we will not heal the
+                                 * gf_file_tb.
+                                 * 2) Rename file in cold tier: During a rename
+                                 * of a file that is there in cold tier. We get
+                                 * an link record created in hot tier for the
+                                 * linkto file. When the file gets heated and
+                                 * moves to hot tier there will be attempt from
+                                 * ctr lookup heal to create link and file
+                                 * record and If we dont ignore the error we
+                                 * will not heal the gf_file_tb.
+                                 * */
                         }
                         gfdb_db_record->islinkupdate = gfdb_db_record->
                                                         link_consistency;