tier/ctr: CTR DB named lookup heal of cold tier during attach tier

Heal hardlink in the db for already existing data in the cold
tier during attach tier. i.e during fix layout do lookup to files
in the cold tier.

CTR xlator on the  brick/server side does db update/insert of the hardlink on a namelookup.
Currently the namedlookup is done synchronous to the fixlayout that is
triggered by attach tier. This is not performant, adding more time to
fixlayout. The performant approach is record the hardlinks on a compressed
datastore and then do the namelookup asynchronously later, giving the ctr db
eventual consistency

master patch : http://review.gluster.org/#/c/11828/

>>Change-Id: I4ffc337fffe7d447804786851a9183a51b5044a9
>>BUG: 1252586
>>Signed-off-by: Joseph Fernandes <josferna@redhat.com>
>>Reviewed-on: http://review.gluster.org/11828
>>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: I61b185a54ae4e8c1d82804b95a278bfbea870987
BUG: 1261146
Reviewed-on: http://review.gluster.org/12331
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>

1 files changed, 122 insertions, 0 deletions

diff --git a/tests/basic/tier/legacy-many.t b/tests/basic/tier/legacy-many.t
new file mode 100644
index 00000000000..17275494aba
--- /dev/null
+++ b/tests/basic/tier/legacy-many.t
@@ -0,0 +1,122 @@
+#!/bin/bash
+
+. $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
+
+LAST_BRICK=3
+CACHE_BRICK_FIRST=4
+CACHE_BRICK_LAST=5
+DEMOTE_TIMEOUT=12
+PROMOTE_TIMEOUT=5
+MIGRATION_TIMEOUT=10
+DEMOTE_FREQ=60
+PROMOTE_FREQ=4
+TEST_DIR="test_files"
+NUM_FILES=20
+
+
+# Grab md5sum without file path (failed attempt notifications are discarded)
+function fingerprint {
+    md5sum $1 2> /dev/null | grep --only-matching -m 1 '^[0-9a-f]*'
+}
+
+# Create a large number of files. Store their md5 signatures.
+function create_many_files {
+    mkdir ${TEST_DIR}
+    for i in `seq 1 $NUM_FILES`; do
+        dd if=/dev/urandom of=./${TEST_DIR}/i$i bs=1048576 count=1;
+        id[i]=$(fingerprint "./${TEST_DIR}/i$i");
+    done
+}
+
+function confirm_tier_removed {
+    $CLI system getspec $V0 | grep $1
+    if [ $? == 0 ]; then
+        echo "1"
+    else
+        echo "0"
+    fi
+}
+
+function confirm_vol_stopped {
+    $CLI volume stop $1
+    if [ $? == 0 ]; then
+        echo "0"
+    else
+        echo "1"
+    fi
+}
+
+function check_counters {
+    index=0
+    ret=0
+    rm -f /tmp/tc*.txt
+    echo "0" > /tmp/tc2.txt
+
+    $CLI volume rebalance $V0 tier status | grep localhost > /tmp/tc.txt
+
+    promote=`cat /tmp/tc.txt |awk '{print $2}'`
+    demote=`cat /tmp/tc.txt |awk '{print $3}'`
+   if [ "${promote}" != "${1}" ]; then
+        echo "1" > /tmp/tc2.txt
+
+   elif [ "${demote}" != "${2}" ]; then
+        echo "2" > /tmp/tc2.txt
+   fi
+
+    # temporarily disable non-Linux tests.
+    case $OSTYPE in
+        NetBSD | FreeBSD | Darwin)
+            echo "0" > /tmp/tc2.txt
+            ;;
+    esac
+    cat /tmp/tc2.txt
+}
+
+function read_all {
+    for file in *
+    do
+        cat $file
+    done
+}
+
+cleanup
+
+TEST glusterd
+TEST pidof glusterd
+
+# Create distributed replica volume
+TEST $CLI volume create $V0 replica 2 $H0:$B0/${V0}{0..$LAST_BRICK}
+TEST $CLI volume start $V0
+
+TEST $CLI volume set $V0 performance.quick-read off
+TEST $CLI volume set $V0 performance.io-cache off
+TEST $CLI volume set $V0 features.ctr-enabled on
+
+TEST $GFS --volfile-id=/$V0 --volfile-server=$H0 $M0;
+
+# Create a number of "legacy" files before attaching tier
+cd $M0
+TEST create_many_files
+wait
+
+# Attach tier
+TEST $CLI volume attach-tier $V0 replica 2 $H0:$B0/${V0}$CACHE_BRICK_FIRST $H0:$B0/${V0}$CACHE_BRICK_LAST
+TEST $CLI volume rebalance $V0 tier status
+
+TEST $CLI volume set $V0 cluster.tier-demote-frequency $DEMOTE_FREQ
+TEST $CLI volume set $V0 cluster.tier-promote-frequency $PROMOTE_FREQ
+TEST $CLI volume set $V0 cluster.read-freq-threshold 0
+TEST $CLI volume set $V0 cluster.write-freq-threshold 0
+
+# Read "legacy" files
+drop_cache $M0
+cd ${TEST_DIR}
+TEST read_all
+
+# Test to make sure files were promoted as expected
+sleep $DEMOTE_TIMEOUT
+EXPECT_WITHIN $DEMOTE_TIMEOUT "0" check_counters 20 0
+
+cd;
+cleanup