Displays detailed information for MapR-DB or file-system components that are identified by an FID.

Only the root user and the MAPR_USER user (user under which MapR services runs) have permissions to run this command.

Syntax

CLImaprcli fid dump
[ -cluster cluster_name ]
-fid fid
RESTN/A

Parameters

ParameterDescription
clusterThe cluster on which to run the command. If this parameter is omitted, the command is run on the same cluster where it is issued. In multi-cluster contexts, you can use this parameter to specify a different cluster on which to run the command.
fidThe file identifier for the element (region, kvstore, etc.) for which you want detailed information. The output of maprcli table region list lists the FIDs for the table's regions.

You can run this command on any FID available on the MapR-FS. The following file types display information that may be useful:

Tablet Map

The maprcli fid dump output for a tablet map includes the key for each tablet and its corresponding FID. Each tablet contain a range of data starting with the key associated with the tablet and ending before the key associated with the next tablet.

To determine the FID for a tablet map:

  1. Run hadoop mfs -ls <table path> to determine the table FID. The table FID is the FID that displays after the "p.”
    Example: 

    [mapr@hostname ~]$ hadoop mfs -ls /testdst
    Found 1 items
    tr-------- Z U 3 mapr mapr 2 2015-02-18 15:24 0 /testdst
    p 2049.49.131220 hostname:5660
    r 2061.32.131258 hostname:5660
  2. Run maprcli fid dump on the table FID to determine the tablet map FID.
    Example:

    [mapr@hostname ~]$ maprcli fid dump -fid 2049.49.131220
    value key
    {"value":{"fid":"<parentCID>.51.131224"}} schema
    {"value":{"fid":"<parentCID>.50.131222"}} tabletmap
  3. Construct the tablet map FID for the maprcli fid dump command by replacing <parentCID> with the set of numbers before the first period four numbers in the table FID. 
    Example: 2049.50.131222

Output Example for a Tablet Map

maprcli fid dump -fid 2049.50.131222 -json
{
 "timestamp":1425579595296,
 "timeofday":"2015-03-05 06:19:55.296 GMT+0000",
 "status":"OK",
 "total":4,
 "data":[
  {
   "key":"",
   "value":{
    "fid":"2116.59.131462"
   }
  },
  {
   "key":"user3155781742051747178",
   "value":{
    "fid":"2114.49.131348"
   }
  },
  {
   "key":"user5238840414188136300",
   "value":{
    "fid":"2118.49.131394"
   }
  },
  {
   "key":"user7257930685533675764",
   "value":{
    "fid":"2115.59.131316"
   }
  }
 ]
}

Tablet

The maprcli fid dump output for a tablet includes key and value pairs for the following:

  • startkey. The first key value in the tablet.
  • pmap. Each partition.
  • endkey. The last key value in the tablet.

Output Fields for a Tablet

This table describes a majority of the output values for each partition (pmap) in the tablet.

FieldDescription
keyThe partition key.
segfidThe FID of the segment map associated with this partition.
isFrozenA Boolean value that indicates if a partition is in a frozen state or not. Internally, a partition is sometimes temporarily marked as frozen in order for certain operations to complete.
inSplitA Boolean value that indicates if a partition split is in progress for this partition.
useBucketDescThis property is for internal use only.

lastFlushedBucketFid

The FID of the bucket file (WAL) which was last flushed for this partition.
numLogicalBlocks

The number of logical blocks (8K) for this partition.

numPhysicalBLocks

The number of physical blocks (8K) for this partition.

numRowsThe number of rows stored in this partition.
numRowsWithDeleteThe number of rows which are marked for delete in this partition.
numRemoteBlocks

The number of disk blocks which are not local to this partition.
When a region splits, a partition moves from one node to another and it is possible to temporarily have some remote blocks.

numSpillsThe number of spills.
numSegmentsThe number of segments.

 

Output Example for a Tablet

maprcli fid dump -fid 2116.59.131462 -json
{
	"timestamp":1425579636931,
	"timeofday":"2015-03-05 06:20:36.931 GMT+0000",
	"status":"OK",
	"total":6,
	"data":[
		{
			"key":"endkey.user3155781742051747178",
			"value":{
				
			}
		},
		{
			"key":"pmap.",
			"value":{
				"segfid":"<parentCID>.1065.133486",
				"isFrozen":false,
				"inSplit":false,
				"useBucketDesc":true,
				"lastFlushedBucketFid":"2116.901.133158",
				"numLogicalBlocks":34921,
				"numPhysicalBlocks":21976,
				"numRows":9332,
				"numRowsWithDelete":0,
				"numRemoteBlocks":0,
				"numSpills":137,
				"numSegments":74
			}
		},
		{
			"key":"pmap.user1523186274532578170",
			"value":{
				"segfid":"<parentCID>.1066.133488",
				"isFrozen":false,
				"inSplit":false,
				"useBucketDesc":true,
				"lastFlushedBucketFid":"2116.902.133160",
				"numLogicalBlocks":37011,
				"numPhysicalBlocks":23260,
				"numRows":9868,
				"numRowsWithDelete":0,
				"numRemoteBlocks":168,
				"numSpills":147,
				"numSegments":78
			}
		},
		{
			"key":"pmap.user2078250355776544396",
			"value":{
				"segfid":"<parentCID>.445.132238",
				"isFrozen":false,
				"inSplit":false,
				"useBucketDesc":true,
				"lastFlushedBucketFid":"2116.447.132242",
				"numLogicalBlocks":71124,
				"numPhysicalBlocks":44797,
				"numRows":18991,
				"numRowsWithDelete":0,
				"numRemoteBlocks":172,
				"numSpills":300,
				"numSegments":152
			}
		},
		{
			"key":"postSplitCopy",
			"value":{
				"raw":"dummy"
			}
		},
		{
			"key":"startkey.",
			"value":{	
			}
		}
	]
}
The postSpitCopy key and value are for internal use only.

Segment Map

The maprcli fid dump output of a segment map includes a map of row keys and the corresponding segment FID.

 Output Fields for a Segment Map

FieldDescription
keyThe row key
valueThe FID corresponding to the segment associated with this key.

Output Example for a Segment Map

maprcli fid dump -fid 2116.1065.133486 -json

{
	"timestamp":1425579702407,
	"timeofday":"2015-03-05 06:21:42.407 GMT+0000",
	"status":"OK",
	"total":74,
	"data":[
		{
			"key":"",
			"value":{
				"fid":"<parentCID>.943.133242"
			}
		},
		{
			"key":"user1006417450462802131",
			"value":{
				"fid":"<parentCID>.945.133246"
			}
		},
...
	]
}

Segment

The output of maprcli fid dump for a segment includes details about each spill.

Output Fields for a Segment

FieldDescription
keyThe index of the spill. 
numRemoteBlocksThe number of remote blocks.
numspillsThe number of spills.
value

The property contains the following values:

  • fid: The FID of the spill containing row and value data.

  • smeSize: The spill map entry size.

  • keyIdxOffset: The offsets and length inside the spill for the index

  • keyIdxLength: The length inside the spill for the index

  • ldbIdxLength: The length of the index portion in the spill.

  • bloomBitsPerKey: The number of bits used in the bloom filter per key.

  • numLogicalBlocks. The number of logical blocks in the spill.

  • numPhysicalBlocks: The number of physical blocks in the spill.

  • numRows: The number of rows in the spill.

  • numRowsWithDelete: The number of rows which are marked for delete in the spill.

  • families:Information about the location of different column family data in the spill and the time range of that data.

Output Example for a Segment

maprcli fid dump -fid  2116.945.133246  -json
{
	"timestamp":1425579733821,
	"timeofday":"2015-03-05 06:22:13.821 GMT+0000",
	"status":"OK",
	"total":1,
	"data":[
		{
			"key":0,
			"numRemoteBlocks":0,
			"numSpills":0,
			"numSegments":0,
			"value":{
				"fid":"<parentCID>.946.133248",
				"smeSize":55,
				"keyIdxOffset":12,
				"keyIdxLength":3587,
				"ldbIdxLength":20,
				"bloomBitsPerKey":80,
				"numLogicalBlocks":369,
				"numPhysicalBlocks":232,
				"numRows":99,
				"numRowsWithDelete":0,
				"families":{
					"id":1,
					"offset":524288,
					"length":2976835,
					"minTimeStamp":1425578650850,
					"maxTimeStamp":1425578856492
				}
			}
		}
	]
}