gsyncd / geo-rep: Introduce basic crawl instrumentation

This patch extends the persistent instrumentation work done by
Aravinda (@avishwa), by introducing a handfull of instrumentation
variables for crawl. These variables are "pulled up" by glusterd
in the event of a geo-replication status cli command and looks
something like below:

"Uptime=00:21:10;FilesSyned=2982;FilesPending=0;BytesPending=0;DeletesPending=0;"

"FilesPending", "BytesPending" and "DeletesPending" are short-lived
variables that are non-zero when a changelog is being processes (ie.
when an active sync in ongoing). After a successfull changelog process
"FilesPending" is summed up into "FilesSynced". The three short-lived
variabled are then reset to zero and the data is persisted

Additionally this patch also reverts some of the changes made for
BZ #986929 (those were not needed).

Change-Id: I948f1a0884ca71bc5e5bcfdc017d16c8c54fc30b
BUG: 990420
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-on: http://review.gluster.org/5441
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

4 files changed, 104 insertions, 80 deletions

diff --git a/geo-replication/syncdaemon/master.py b/geo-replication/syncdaemon/master.py
index 12eadb1073a..cf2f7db0706 100644
--- a/geo-replication/syncdaemon/master.py
+++ b/geo-replication/syncdaemon/master.py
@@ -17,7 +17,8 @@ from datetime import datetime
 from gconf import gconf
 from tempfile import mkdtemp, NamedTemporaryFile
 from syncdutils import FreeObject, Thread, GsyncdError, boolify, escape, \
-                       unescape, select, gauxpfx, md5hex, selfkill, entry2pb
+                       unescape, select, gauxpfx, md5hex, selfkill, entry2pb, \
+                       lstat
 
 URXTIME = (-1, 0)
 
@@ -380,7 +381,13 @@ class GMasterCommon(object):
         return self.xtime_low(rsc.server, path, **opts)
 
     def get_initial_crawl_data(self):
-        default_data = {'sync_time': 0, 'files_synced': 0, 'bytes_synced': 0}
+        # while persisting only 'files_syncd' is non-zero, rest of
+        # the stats are nulls. lets keep it that way in case they
+        # are needed to be used some day...
+        default_data = {'files_syncd': 0,
+                        'files_remaining': 0,
+                        'bytes_remaining': 0,
+                        'purges_remaining': 0}
         if getattr(gconf, 'state_detail_file', None):
             try:
                 return json.load(open(gconf.state_detail_file))
@@ -393,7 +400,6 @@ class GMasterCommon(object):
                     return default_data
                 else:
                     raise
-
         return default_data
 
     def update_crawl_data(self):
@@ -422,10 +428,9 @@ class GMasterCommon(object):
         self.crawls = 0
         self.turns = 0
         self.total_turns = int(gconf.turns)
+        self.crawl_start = datetime.now()
         self.lastreport = {'crawls': 0, 'turns': 0, 'time': 0}
-        self.crawl_stats = {'sync_time': 0, 'last_synctime': 0, 'crawl_starttime': 0,
-                            'crawl_time': 0, 'files_synced': 0, 'bytes_synced' :0}
-        self.total_crawl_stats = self.get_initial_crawl_data()
+        self.total_crawl_stats = None
         self.start = None
         self.change_seen = None
         # the authoritative (foreign, native) volinfo pair
@@ -491,9 +496,8 @@ class GMasterCommon(object):
             # for a passive gsyncd (ie. in a replicate scenario)
             # the keepalive thread would keep the connection alive.
             self.init_keep_alive()
+	self.total_crawl_stats = self.get_initial_crawl_data()
         self.lastreport['time'] = time.time()
-        self.crawl_stats['crawl_starttime'] = datetime.now()
-
         logging.info('crawl interval: %d seconds' % self.sleep_interval)
         t0 = time.time()
         crawl = self.should_crawl()
@@ -556,17 +560,13 @@ class GMasterCommon(object):
         return ts
 
     def get_extra_info(self):
-        str_info = "\nFilesSynced=%d;" % (self.crawl_stats['files_synced'])
-        str_info += "BytesSynced=%s;" % (self.crawl_stats['bytes_synced'])
-
-        self.crawl_stats['crawl_time'] = datetime.now() - self.crawl_stats['crawl_starttime']
-
-        str_info += "Uptime=%s;" % (self._crawl_time_format(self.crawl_stats['crawl_time']))
-        str_info += "SyncTime=%s;" % (self.crawl_stats['sync_time'])
-        str_info += "TotalSyncTime=%s;" % (self.total_crawl_stats['sync_time'])
-        str_info += "TotalFilesSynced=%d;" % (self.total_crawl_stats['files_synced'])
-        str_info += "TotalBytesSynced=%s;" % (self.total_crawl_stats['bytes_synced'])
-        str_info += "\0"
+        str_info = '\nUptime=%s;FilesSyncd=%d;FilesPending=%d;BytesPending=%d;DeletesPending=%d;' % \
+            (self._crawl_time_format(datetime.now() - self.crawl_start), \
+                 self.total_crawl_stats['files_syncd'], \
+                 self.total_crawl_stats['files_remaining'], \
+                 self.total_crawl_stats['bytes_remaining'], \
+                 self.total_crawl_stats['purges_remaining'])
+        str_info += '\0'
         logging.debug(str_info)
         return str_info
 
@@ -788,15 +788,11 @@ class GMasterChangelogMixin(GMasterCommon):
         logging.debug('changelog working dir %s (log: %s)' % (workdir, logfile))
         return (workdir, logfile)
 
-    def lstat(self, e):
-        try:
-            return os.lstat(e)
-        except (IOError, OSError):
-            ex = sys.exc_info()[1]
-            if ex.errno == ENOENT:
-                return ex.errno
-            else:
-                raise
+    # update stats from *this* crawl
+    def update_cumulative_stats(self, files_pending):
+        self.total_crawl_stats['files_remaining']  = files_pending['count']
+        self.total_crawl_stats['bytes_remaining']  = files_pending['bytes']
+        self.total_crawl_stats['purges_remaining'] = files_pending['purge']
 
     # sync data
     def syncdata(self, datas):
@@ -804,43 +800,31 @@ class GMasterChangelogMixin(GMasterCommon):
         for data in datas:
             logging.debug('candidate for syncing %s' % data)
             pb = self.syncer.add(data)
-            timeA = datetime.now()
             def regjob(se, xte, pb):
                 rv = pb.wait()
                 if rv[0]:
                     logging.debug('synced ' + se)
-                    # update stats
-                    timeB = datetime.now()
-                    self.crawl_stats['last_synctime'] = timeB - timeA
-                    self.crawl_stats['sync_time'] += ((self.crawl_stats['last_synctime'].microseconds) / (10.0 ** 6))
-                    self.crawl_stats['files_synced'] += 1
-                    self.crawl_stats['bytes_synced'] += self.syncer.bytes_synced
-
-                    # cumulative statistics
-                    self.total_crawl_stats['bytes_synced'] += self.syncer.bytes_synced
-                    self.total_crawl_stats['sync_time'] += ((self.crawl_stats['last_synctime'].microseconds) / (10.0 ** 6))
-                    self.total_crawl_stats['files_synced'] += 1
                     return True
                 else:
                     if rv[1] in [23, 24]:
                         # stat to check if the file exist
-                        st = self.lstat(se)
+                        st = lstat(se)
                         if isinstance(st, int):
                             # file got unlinked in the interim
                             return True
                     logging.warn('Rsync: %s [errcode: %d]' % (se, rv[1]))
             self.add_job(self.FLAT_DIR_HIERARCHY, 'reg', regjob, data, None, pb)
         if self.wait(self.FLAT_DIR_HIERARCHY, None):
-            self.update_crawl_data()
             return True
 
-    def process_change(self, change, done):
+    def process_change(self, change, done, retry):
+        pfx = gauxpfx()
         clist   = []
         entries = []
-        purges = set()
-        links = set()
         datas = set()
-        pfx = gauxpfx()
+
+        # basic crawl stats: files and bytes
+        files_pending  = {'count': 0, 'purge': 0, 'bytes': 0, 'files': []}
         try:
             f = open(change, "r")
             clist = f.readlines()
@@ -861,6 +845,27 @@ class GMasterChangelogMixin(GMasterCommon):
                 else:
                     dct[k] = ed[k]
             return dct
+
+        # regular file update: bytes & count
+        def _update_reg(entry, size):
+            if not entry in files_pending['files']:
+                files_pending['count'] += 1
+                files_pending['bytes'] += size
+                files_pending['files'].append(entry)
+        # updates for directories, symlinks etc..
+        def _update_rest():
+            files_pending['count'] += 1
+
+        # entry count
+        def entry_update(entry, size, mode):
+            if stat.S_ISREG(mode):
+                _update_reg(entry, size)
+            else:
+                _update_rest()
+        # purge count
+        def purge_update():
+            files_pending['purge'] += 1
+
         for e in clist:
             e = e.strip()
             et = e[self.IDX_START:self.IDX_END]
@@ -871,20 +876,19 @@ class GMasterChangelogMixin(GMasterCommon):
                 gfid = ec[self.POS_GFID]
                 # definitely need a better way bucketize entry ops
                 if ty in ['UNLINK', 'RMDIR']:
-                  entries.append(edct(ty, gfid=gfid, entry=en))
-                  purges.update([os.path.join(pfx, gfid)])
-                  continue
-                if not ty == 'RENAME':
-                    go = os.path.join(pfx, gfid)
-                    st = self.lstat(go)
-                    if isinstance(st, int):
-                        logging.debug('file %s got purged in the interim' % go)
-                        continue
+                    purge_update()
+                    entries.append(edct(ty, gfid=gfid, entry=en))
+                    continue
+                go = os.path.join(pfx, gfid)
+                st = lstat(go)
+                if isinstance(st, int):
+                    logging.debug('file %s got purged in the interim' % go)
+                    continue
+                entry_update(go, st.st_size, st.st_mode)
                 if ty in ['CREATE', 'MKDIR', 'MKNOD']:
                     entries.append(edct(ty, stat=st, entry=en, gfid=gfid))
                 elif ty == 'LINK':
                     entries.append(edct(ty, stat=st, entry=en, gfid=gfid))
-                    links.update([os.path.join(pfx, gfid)])
                 elif ty == 'SYMLINK':
                     entries.append(edct(ty, stat=st, entry=en, gfid=gfid, link=os.readlink(en)))
                 elif ty == 'RENAME':
@@ -893,30 +897,41 @@ class GMasterChangelogMixin(GMasterCommon):
                 else:
                     pass
             elif et in self.TYPE_GFID:
-                da = os.path.join(pfx, ec[0])
-                st = self.lstat(da)
+                go = os.path.join(pfx, ec[0])
+                st = lstat(go)
                 if isinstance(st, int):
-                    logging.debug('file %s got purged in the interim' % da)
+                    logging.debug('file %s got purged in the interim' % go)
                     continue
-                datas.update([da])
+                entry_update(go, st.st_size, st.st_mode)
+                datas.update([go])
         logging.debug('entries: %s' % repr(entries))
+        if not retry:
+            self.update_cumulative_stats(files_pending)
         # sync namespace
         if (entries):
             self.slave.server.entry_ops(entries)
         # sync data
-        if self.syncdata(datas - (purges - links)):
+        if self.syncdata(datas):
             if done:
                 self.master.server.changelog_done(change)
             return True
 
+    def sync_done(self):
+        self.total_crawl_stats['files_syncd'] += self.total_crawl_stats['files_remaining']
+        self.total_crawl_stats['files_remaining']  = 0
+        self.total_crawl_stats['bytes_remaining']  = 0
+        self.total_crawl_stats['purges_remaining'] = 0
+        self.update_crawl_data()
+
     def process(self, changes, done=1):
         for change in changes:
-            times = 0
+            retry = False
             while True:
-                times += 1
-                logging.debug('processing change %s [%d time(s)]' % (change, times))
-                if self.process_change(change, done):
+                logging.debug('processing change %s' % change)
+                if self.process_change(change, done, retry):
+                    self.sync_done()
                     break
+                retry = True
                 # it's either entry_ops() or Rsync that failed to do it's
                 # job. Mostly it's entry_ops() [which currently has a problem
                 # of failing to create an entry but failing to return an errno]
@@ -1032,7 +1047,7 @@ class GMasterXsyncMixin(GMasterChangelogMixin):
         for e in dem:
             bname = e
             e = os.path.join(path, e)
-            st = self.lstat(e)
+            st = lstat(e)
             if isinstance(st, int):
                 logging.warn('%s got purged in the interim..' % e)
                 continue
@@ -1191,19 +1206,10 @@ class GMasterXtimeMixin(GMasterCommon):
             elif stat.S_ISREG(mo):
                 logging.debug("syncing %s ..." % e)
                 pb = self.syncer.add(e)
-                timeA = datetime.now()
                 def regjob(e, xte, pb):
                     if pb.wait()[0]:
                         logging.debug("synced " + e)
                         self.sendmark_regular(e, xte)
-                        # update stats
-                        timeB = datetime.now()
-                        self.crawl_stats['last_synctime'] = timeB - timeA
-                        self.crawl_stats['sync_time'] += ((self.crawl_stats['last_synctime'].microseconds) / (10.0 ** 6))
-                        self.crawl_stats['files_synced'] += 1
-                        self.total_crawl_stats['sync_time'] += ((self.crawl_stats['last_synctime'].microseconds) / (10.0 ** 6))
-                        self.total_crawl_stats['files_synced'] += 1
-                        self.update_crawl_data()
                         return True
                     else:
                         logging.warn("failed to sync " + e)
diff --git a/geo-replication/syncdaemon/resource.py b/geo-replication/syncdaemon/resource.py
index 1010247aed1..2357b4f914c 100644
--- a/geo-replication/syncdaemon/resource.py
+++ b/geo-replication/syncdaemon/resource.py
@@ -21,7 +21,7 @@ from repce import RepceServer, RepceClient
 from  master import gmaster_builder
 import syncdutils
 from syncdutils import GsyncdError, select, privileged, boolify, funcode
-from syncdutils import umask, entry2pb, gauxpfx, errno_wrap
+from syncdutils import umask, entry2pb, gauxpfx, errno_wrap, lstat
 
 UrlRX  = re.compile('\A(\w+)://([^ *?[]*)\Z')
 HostRX = re.compile('[a-z\d](?:[a-z\d.-]*[a-z\d])?', re.I)
@@ -514,12 +514,20 @@ class Server(object):
             elif op == 'MKDIR':
                 blob = entry_pack_mkdir(gfid, bname, e['stat'])
             elif op == 'LINK':
-                errno_wrap(os.link, [os.path.join(pfx, gfid), entry], [ENOENT, EEXIST])
+                st = lstat(entry)
+                if isinstance(st, int):
+                    blob = entry_pack_reg(gfid, bname, e['stat'])
+                else:
+                    errno_wrap(os.link, [os.path.join(pfx, gfid), entry], [ENOENT, EEXIST])
             elif op == 'SYMLINK':
                 blob = entry_pack_symlink(gfid, bname, e['link'], e['stat'])
             elif op == 'RENAME':
                 en = e['entry1']
-                errno_wrap(os.rename, [entry, en], [ENOENT, EEXIST])
+                st = lstat(entry)
+                if isinstance(st, int):
+                    blob = entry_pack_reg(gfid, bname, e['stat'])
+                else:
+                    errno_wrap(os.rename, [entry, en], [ENOENT, EEXIST])
             if blob:
                 errno_wrap(Xattr.lsetxattr_l, [pg, 'glusterfs.gfid.newfile', blob], [ENOENT, EEXIST])
 
diff --git a/geo-replication/syncdaemon/syncdutils.py b/geo-replication/syncdaemon/syncdutils.py
index c09b2505ddd..2655dd9835e 100644
--- a/geo-replication/syncdaemon/syncdutils.py
+++ b/geo-replication/syncdaemon/syncdutils.py
@@ -419,3 +419,13 @@ def errno_wrap(call, arg=[], errnos=[]):
             if not ex.errno == ESTALE:
                 raise
             time.sleep(0.5)  # retry the call
+
+def lstat(e):
+    try:
+        return os.lstat(e)
+    except (IOError, OSError):
+        ex = sys.exc_info()[1]
+        if ex.errno == ENOENT:
+            return ex.errno
+        else:
+            raise
diff --git a/xlators/features/changelog/src/changelog.c b/xlators/features/changelog/src/changelog.c
index fe064342911..0e85ee7a0ab 100644
--- a/xlators/features/changelog/src/changelog.c
+++ b/xlators/features/changelog/src/changelog.c
@@ -203,7 +203,6 @@ changelog_rename (call_frame_t *frame, xlator_t *this,
                   loc_t *oldloc, loc_t *newloc, dict_t *xdata)
 {
         size_t            xtra_len  = 0;
-        uuid_t            null_uuid = {0,};
         changelog_priv_t *priv      = NULL;
         changelog_opt_t  *co        = NULL;
 
@@ -211,7 +210,8 @@ changelog_rename (call_frame_t *frame, xlator_t *this,
         CHANGELOG_NOT_ACTIVE_THEN_GOTO (frame, priv, wind);
 
         /* 3 == fop + oldloc + newloc */
-        CHANGELOG_INIT_NOCHECK (this, frame->local, NULL, null_uuid, 3);
+        CHANGELOG_INIT_NOCHECK (this, frame->local,
+                                NULL, oldloc->inode->gfid, 3);
 
         co = changelog_get_usable_buffer (frame->local);
         if (!co)