How to check Memory and Index Usage in MySQL CLuster,on the management Node connect to ndb_mgm client utility

run /usr/bin/ndb_mgm

output
– NDB Cluster — Management Client –

run show command
ndb_mgm> show

Connected to Management Server at: localhost:1186
Cluster Configuration
———————
[ndbd(NDB)]     2 node(s)
id=2    @xx.xxx.xx.xxx  (mysql-5.1.47 ndb-7.1.8, Nodegroup: 0, Master)
id=3    @yy.yyy.yy.yyy  (mysql-5.1.47 ndb-7.1.8, Nodegroup: 0)

[ndb_mgmd(MGM)] 1 node(s)
id=1    @zz.zzz.zz.zzz  (mysql-5.1.47 ndb-7.1.8)

[mysqld(API)]   1 node(s)
id=4    @bb.bb.bb.bb  (mysql-5.1.47 ndb-7.1.8)

now this setup has 2 data nodes to check the Memory and Index Usage for node 2

ndb_mgm> 2 REPORT MemoryUsage;
Node 2: Data usage is 5%(3846 32K pages of total 65536)
Node 2: Index usage is 0%(229 8K pages of total 131104)

this will give you two things how much in percentage used and how much total memory we have allocated
Memory : 32K*65536  (32k data page size and 65536 no of pages
INdex  : 8k*131104  (8K data page size and 131104 no of blocks)