From 527c297efb16694f0239ea221a226afecaf310d2 Mon Sep 17 00:00:00 2001
From: Oran Agra <oran@redislabs.com>
Date: Thu, 4 Jul 2019 10:02:26 +0300
Subject: [PATCH] missing per-skiplist overheads in MEMORY USAGE

these had severe impact for small zsets, for instance ones with just one
element that is longer than 64 (causing it not to be ziplist encoded)
---
 src/object.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/object.c b/src/object.c
index 234e11f8a..10209a6c8 100644
--- a/src/object.c
+++ b/src/object.c
@@ -834,7 +834,9 @@ size_t objectComputeSize(robj *o, size_t sample_size) {
             d = ((zset*)o->ptr)->dict;
             zskiplist *zsl = ((zset*)o->ptr)->zsl;
             zskiplistNode *znode = zsl->header->level[0].forward;
-            asize = sizeof(*o)+sizeof(zset)+(sizeof(struct dictEntry*)*dictSlots(d));
+            asize = sizeof(*o)+sizeof(zset)+sizeof(zskiplist)+sizeof(dict)+
+                    (sizeof(struct dictEntry*)*dictSlots(d))+
+                    zmalloc_size(zsl->header);
             while(znode != NULL && samples < sample_size) {
                 elesize += sdsAllocSize(znode->ele);
                 elesize += sizeof(struct dictEntry) + zmalloc_size(znode);