cluster/ec: Implement gfid-hash read-policy

Add a policy in ec to performs reads from same bricks as long as they
are good. Based on the gfid of the file/directory it determines the
bricks to be considered for reading.

Change-Id: Ic97b5c54c086a28b5e07a330a4fd448551b49376
BUG: 1261260
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/12133
Tested-by: NetBSD Build System <jenkins@build.gluster.org>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Xavier Hernandez <xhernandez@datalab.es>

1 files changed, 53 insertions, 0 deletions

diff --git a/tests/basic/ec/ec-read-policy.t b/tests/basic/ec/ec-read-policy.t
new file mode 100644
index 00000000000..891508063e6
--- /dev/null
+++ b/tests/basic/ec/ec-read-policy.t
@@ -0,0 +1,53 @@
+#!/bin/bash
+
+. $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
+
+cleanup
+
+TEST glusterd
+TEST pidof glusterd
+TEST $CLI volume create $V0 disperse 6 redundancy 2 $H0:$B0/${V0}{0..5}
+TEST $CLI volume set $V0 performance.quick-read off
+TEST $CLI volume set $V0 performance.io-cache off
+TEST $CLI volume set $V0 performance.write-behind off
+TEST $CLI volume set $V0 performance.stat-prefetch off
+TEST $CLI volume set $V0 performance.read-ahead off
+TEST $CLI volume heal $V0 disable
+TEST $CLI volume start $V0
+
+#Disable all caching
+TEST glusterfs --direct-io-mode=yes --entry-timeout=0 --attribute-timeout=0 -s $H0 --volfile-id $V0 $M0
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "6" ec_child_up_count $V0 0
+#TEST volume operations work fine
+EXPECT "round-robin" mount_get_option_value $M0 $V0-disperse-0 read-policy
+TEST $CLI volume set $V0 disperse.read-policy gfid-hash
+EXPECT_WITHIN $CONFIG_UPDATE_TIMEOUT "gfid-hash" mount_get_option_value $M0 $V0-disperse-0 read-policy
+TEST $CLI volume reset $V0 disperse.read-policy
+EXPECT_WITHIN $CONFIG_UPDATE_TIMEOUT "round-robin" mount_get_option_value $M0 $V0-disperse-0 read-policy
+
+#TEST if the option gives the intended behavior. The way we perform this test
+#is by performing reads from the mount and write to /dev/null. If the
+#read-policy is round-robin, then all bricks should have read-fop where as
+#with gfid-hash number of bricks with reads should be equal to (num-bricks - redundancy)
+#count
+
+TEST $CLI volume profile $V0 start
+TEST dd if=/dev/zero of=$M0/1 bs=1M count=4
+#Perform reads now from file on the mount, this only tests dispatch_min
+TEST dd if=$M0/1 of=/dev/null bs=1M count=4
+#TEST that reads are executed on all bricks
+rr_reads=$($CLI volume profile $V0 info cumulative| grep READ | wc -l)
+EXPECT "^6$" echo $rr_reads
+TEST $CLI volume profile $V0 info clear
+
+TEST $CLI volume set $V0 disperse.read-policy gfid-hash
+EXPECT_WITHIN $CONFIG_UPDATE_TIMEOUT "gfid-hash" mount_get_option_value $M0 $V0-disperse-0 read-policy
+
+#Perform reads now from file on the mount, this only tests dispatch_min
+TEST dd if=$M0/1 of=/dev/null bs=1M count=4
+#TEST that reads are executed on all bricks
+gh_reads=$($CLI volume profile $V0 info cumulative| grep READ |  wc -l)
+EXPECT "^4$" echo $gh_reads
+
+cleanup;