This patch helps to distribute load across an afr cluster when you have clients with the same access patterns, such as in benchmarking or map-reduce. By randomly offsetting the initial read_child_rr, clients should distribute reads over the afr nodes on average. A better solution could be to randomly shuffle the children instead of chosing a different initial offset. This should average the reads better across the nodes, but I'm not sure if there are any other consequences to doing this. --- xlators/cluster/afr/src/afr.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/xlators/cluster/afr/src/afr.c b/xlators/cluster/afr/src/afr.c index a94f926..118e0fc 100644 --- a/xlators/cluster/afr/src/afr.c +++ b/xlators/cluster/afr/src/afr.c @@ -2494,6 +2494,9 @@ init (xlator_t *this) i++; } + /* Randomly pick the starting read child */ + priv->read_child_rr = random() % priv->child_count; + ret = 0; out: return ret; -- 1.6.3.1
