- Code
data_node_id
2350operation_filters
- Symbol
---
- Kernel Block
---
Description. Dumps all operations on a given data node or data nodes, according to the type and other parameters defined by the operation filter or filters specified.
Sample Output. Dump all operations on data node 2, from API node 5:
ndb_mgm> 2 DUMP 2350 1 5
2011-11-01 13:16:49 [MgmSrvr] INFO -- Node 2: Starting dump of operations
2011-11-01 13:16:49 [MgmSrvr] INFO -- Node 2: OP[470]:
Tab: 4 frag: 0 TC: 3 API: 5(0x8035)transid: 0x31c 0x3500500 op: SCAN state: InQueue
2011-11-01 13:16:49 [MgmSrvr] INFO -- Node 2: End of operation dump
Additional information. Information about operation filter and operation state values follows.
Operation filter values. The operation filter (or filters) can take on the following values:
Table 2.7 Filter values
Value | Filter |
---|---|
0 | table ID |
1 | API node ID |
2 | 2 transaction IDs, defining a range of transactions |
3 | transaction coordinator node ID |
In each case, the ID of the object specified follows the specifier. See the sample output for examples.
Operation states. The “normal” states that may appear in the output from this command are listed here:
-
Transactions:
Prepared
: The transaction coordinator is idle, waiting for the API to proceedRunning
: The transaction coordinator is currently preparing operationsCommitting
,Prepare to commit
,Commit sent
: The transaction coordinator is committingCompleting
: The transaction coordinator is completing the commit (after commit, some cleanup is needed)Aborting
: The transaction coordinator is aborting the transactionScanning
: The transaction coordinator is scanning
-
Scan operations:
WaitNextScan
: The scan is idle, waiting for APIInQueue
: The scan has not yet started, but rather is waiting in queue for other scans to complete
-
Primary key operations:
In lock queue
: The operation is waiting on a lockRunning
: The operation is being preparedPrepared
: The operation is prepared, holding an appropriate lock, and waiting for commit or rollback to complete
Relation to NDB API.
It is possible to match the output of DUMP
2350
to specific threads or
Ndb
objects. First suppose that
you dump all operations on data node 2 from API node 5, using
table 4 only, like this:
ndb_mgm> 2 DUMP 2350 1 5 0 4
2011-11-01 13:16:49 [MgmSrvr] INFO -- Node 2: Starting dump of operations
2011-11-01 13:16:49 [MgmSrvr] INFO -- Node 2: OP[470]:
Tab: 4 frag: 0 TC: 3 API: 5(0x8035)transid: 0x31c 0x3500500 op: SCAN state: InQueue
2011-11-01 13:16:49 [MgmSrvr] INFO -- Node 2: End of operation dump
Suppose you are working with an
Ndb
instance named
MyNdb
, to which this operation belongs. You can
see that this is the case by calling the
Ndb
object'
getReference()
method, like
this:
printf("MyNdb.getReference(): 0x%x\n", MyNdb.getReference());
The output from the preceding line of code is:
MyNdb.getReference(): 0x80350005
The high 16 bits of the value shown corresponds to the number in
parentheses from the OP
line in the
DUMP
command' output (8035). For more
about this method, see Ndb::getReference().