diff options
| -rw-r--r-- | src/rpc/layout.rs | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/src/rpc/layout.rs b/src/rpc/layout.rs index 73b356ad..b9c02c21 100644 --- a/src/rpc/layout.rs +++ b/src/rpc/layout.rs @@ -245,8 +245,13 @@ impl ClusterLayout { let mut option = None; for (i, part) in partitions.iter_mut().enumerate() { for (irm, (idrm, _)) in part.nodes.iter().enumerate() { - let suprm = partitions_per_node.get(*idrm).cloned().unwrap_or(0) as i32 - - target_partitions_per_node.get(*idrm).cloned().unwrap_or(0) as i32; + let errratio = |node, parts| { + let tgt = *target_partitions_per_node.get(node).unwrap() as f32; + (parts - tgt) / tgt + }; + let square = |x| x * x; + + let partsrm = partitions_per_node.get(*idrm).cloned().unwrap_or(0) as f32; for (idadd, infoadd) in configured_nodes.iter() { // skip replacing a node by itself @@ -255,14 +260,12 @@ impl ClusterLayout { continue; } - let supadd = partitions_per_node.get(*idadd).cloned().unwrap_or(0) as i32 - - target_partitions_per_node.get(*idadd).cloned().unwrap_or(0) as i32; - // We want to try replacing node idrm by node idadd // if that brings us close to our goal. - let square = |i: i32| i * i; - let oldcost = square(suprm) + square(supadd); - let newcost = square(suprm - 1) + square(supadd + 1); + let partsadd = partitions_per_node.get(*idadd).cloned().unwrap_or(0) as f32; + let oldcost = square(errratio(*idrm, partsrm) - errratio(*idadd, partsadd)); + let newcost = + square(errratio(*idrm, partsrm - 1.) - errratio(*idadd, partsadd + 1.)); if newcost >= oldcost { // not closer to our goal continue; @@ -315,7 +318,9 @@ impl ClusterLayout { // Show statistics println!("New number of partitions per node:"); for (node, npart) in partitions_per_node.iter() { - println!("{:?}\t{}", node, npart); + let tgt = *target_partitions_per_node.get(node).unwrap(); + let pct = 100f32 * (*npart as f32) / (tgt as f32); + println!("{:?}\t{}\t({}% of {})", node, npart, pct as i32, tgt); } println!(); |