From e9629e148bb445474e172134c1bc0d248adf2454 Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Thu, 15 Sep 2016 17:33:11 +0200
Subject: [PATCH] MEMORY command: HELP + dataset percentage (like in INFO).

---
 src/object.c | 21 ++++++++++++++++++---
 src/server.c |  6 +-----
 src/server.h |  1 +
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/src/object.c b/src/object.c
index e47d663e0..02d023248 100644
--- a/src/object.c
+++ b/src/object.c
@@ -936,6 +936,12 @@ struct redisMemOverhead *getMemoryOverheadData(void) {
 
     mh->overhead_total = mem_total;
     mh->dataset = zmalloc_used - mem_total;
+
+    size_t net_usage = 1;
+    if (zmalloc_used > mh->startup_allocated)
+        net_usage = zmalloc_used - mh->startup_allocated;
+    mh->dataset_perc = (float)mh->dataset*100/net_usage;
+
     return mh;
 }
 
@@ -974,7 +980,7 @@ void memoryCommand(client *c) {
     } else if (!strcasecmp(c->argv[1]->ptr,"overhead") && c->argc == 2) {
         struct redisMemOverhead *mh = getMemoryOverheadData();
 
-        addReplyMultiBulkLen(c,(8+mh->num_dbs)*2);
+        addReplyMultiBulkLen(c,(9+mh->num_dbs)*2);
 
         addReplyBulkCString(c,"total.allocated");
         addReplyLongLong(c,mh->total_allocated);
@@ -1010,11 +1016,20 @@ void memoryCommand(client *c) {
         addReplyBulkCString(c,"overhead.total");
         addReplyLongLong(c,mh->overhead_total);
 
-        addReplyBulkCString(c,"dataset");
+        addReplyBulkCString(c,"dataset.bytes");
         addReplyLongLong(c,mh->dataset);
 
+        addReplyBulkCString(c,"dataset.percentage");
+        addReplyDouble(c,mh->dataset_perc);
+
         freeMemoryOverheadData(mh);
+    } else if (!strcasecmp(c->argv[1]->ptr,"help") && c->argc == 2) {
+        addReplyMultiBulkLen(c,2);
+        addReplyBulkCString(c,
+        "MEMORY USAGE <key> [SAMPLES <count>] - Estimate memory usage of key");
+        addReplyBulkCString(c,
+        "MEMORY OVERHEAD                      - Show memory usage details");
     } else {
-        addReplyError(c,"Syntax error. Try MEMORY [usage <key>] | [overhead]");
+        addReplyError(c,"Syntax error. Try MEMORY HELP");
     }
 }
diff --git a/src/server.c b/src/server.c
index fbc2b0a4d..556ea965b 100644
--- a/src/server.c
+++ b/src/server.c
@@ -2828,10 +2828,6 @@ sds genRedisInfoString(char *section) {
         bytesToHuman(used_memory_rss_hmem,server.resident_set_size);
         bytesToHuman(maxmemory_hmem,server.maxmemory);
 
-        size_t net_usage = 1;
-        if (zmalloc_used > mh->startup_allocated)
-            net_usage = zmalloc_used - mh->startup_allocated;
-
         if (sections++) info = sdscat(info,"\r\n");
         info = sdscatprintf(info,
             "# Memory\r\n"
@@ -2864,7 +2860,7 @@ sds genRedisInfoString(char *section) {
             mh->overhead_total,
             mh->startup_allocated,
             mh->dataset,
-            (float)mh->dataset*100/net_usage,
+            mh->dataset_perc,
             (unsigned long)total_system_mem,
             total_system_hmem,
             memory_lua,
diff --git a/src/server.h b/src/server.h
index fb094507b..3f2028f83 100644
--- a/src/server.h
+++ b/src/server.h
@@ -780,6 +780,7 @@ struct redisMemOverhead {
     size_t aof_buffer;
     size_t overhead_total;
     size_t dataset;
+    float dataset_perc;
     size_t num_dbs;
     struct {
         size_t dbid;