--- zabbix-1.6.6/src/libs/zbxsysinfo/linux/memory.c	2009-08-26 15:16:24.000000000 +0200
+++ zabbix-1.6.6/src/libs/zbxsysinfo/linux/memory.c.orig	2009-12-07 13:45:30.000000000 +0200
@@ -151,6 +151,34 @@
 	}
 }
 
+static int	VM_MEMORY_USED(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result)
+{
+	AGENT_RESULT	result_tmp;
+	zbx_uint64_t	tot_val = 0;
+	zbx_uint64_t	free_val = 0;
+
+	assert(result);
+
+	init_result(result);
+	init_result(&result_tmp);
+
+	if(VM_MEMORY_TOTAL(cmd,param,flags,&result_tmp) != SYSINFO_RET_OK ||
+		!(result_tmp.type & AR_UINT64))
+			return SYSINFO_RET_FAIL;
+	tot_val = result_tmp.ui64;
+
+	if (VM_MEMORY_FREE(cmd, param, flags, &result_tmp) != SYSINFO_RET_OK ||
+		!(result_tmp.type & AR_UINT64))
+			return  SYSINFO_RET_FAIL;
+	free_val = result_tmp.ui64;
+
+	free_result(&result_tmp);
+
+	SET_DBL_RESULT(result, (double)tot_val - (double)free_val);
+
+	return SYSINFO_RET_OK;
+}
+
 static int      VM_MEMORY_PFREE(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result)
 {
 	AGENT_RESULT	result_tmp;
@@ -236,6 +264,7 @@
 		{"buffers",	VM_MEMORY_BUFFERS},
 		{"cached",	VM_MEMORY_CACHED},
 		{"available",	VM_MEMORY_AVAILABLE},
+		{"used",	VM_MEMORY_USED},
 		{0,	0}
 	};
         char    mode[MAX_STRING_LEN];