From cc6bae3363b582e4a29c696daf48ad3346823761 Mon Sep 17 00:00:00 2001
From: Erin Swenson-Healey <l@s3r.me>
Date: Thu, 20 Jun 2019 14:05:20 -0700
Subject: [PATCH] bug(allocate once, not thrice) (#6)

---
 sector-builder/src/helpers/snapshots.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sector-builder/src/helpers/snapshots.rs b/sector-builder/src/helpers/snapshots.rs
index e7a74f3..4d4ad7d 100644
--- a/sector-builder/src/helpers/snapshots.rs
+++ b/sector-builder/src/helpers/snapshots.rs
@@ -40,7 +40,7 @@ pub fn load_snapshot<T: KeyValueStore>(
 impl From<&SnapshotKey> for Vec<u8> {
     fn from(n: &SnapshotKey) -> Self {
         // convert the sector size to a byte vector
-        let mut snapshot_key = vec![];
+        let mut snapshot_key = Vec::with_capacity(n.prover_id.len() + 8);
         snapshot_key
             .write_u64::<LittleEndian>(u64::from(n.sector_size))
             .unwrap();