This is my config file from logstash:
input {
	file {
		type => "json"
		path => "[/root/tmp/meminfo/*.json]"
		codec => json
	}
}

output {
	stdout {
	 }

	elasticsearch_http {
		host => "localhost"
		index => "logstash-meminfo-%{+YYYY.MM.dd}"
	}

}


This is my JSON FILE, Time is unix timestamp:
{"Time": 1414672086.0, "SwapTotal": "     5177336 kB", "SwapFree": "      4992196 kB", "MemFree": "        221896 kB", "HighTotal": "     2228160 kB", "Committed_AS": "  2549980 kB", "VmallocChunk": "   100376 kB", "Writeback": "           0 kB", "MemTotal": "      3115180 kB", "VmallocUsed": "      5960 kB", "HugePages_Free": "      0", "Active": "        1657312 kB", "CommitLimit": "   6734924 kB", "Hugepagesize": "     2048 kB", "Name": "MemoryInfo", "Cached": "        2693264 kB", "SwapCached": "       3108 kB", "LowTotal": "       887020 kB", "Dirty": "             112 kB", "Mapped": "         458428 kB", "HighFree": "         1024 kB", "VmallocTotal": "   106488 kB", "Inactive": "      1175632 kB", "PageTables": "      12152 kB", "HugePages_Total": "     0", "Slab": "            31832 kB", "Buffers": "         16468 kB", "LowFree": "