SQL> @latch_sleeps

LATCH TYPE                          IMPACT SLEEP RATE WAITS HOLDING   LEVEL
------------------------------ ----------- ---------- ------------- -------
library cache                        11224      0.03%           256       5
cache buffers chains                  1295      0.00%             0       1
redo allocation                        713      0.01%          9613       7
system commit number                   373      0.00%            66       8
enqueue hash chains                    221      0.00%             3       4
redo copy                              210     22.30%             0       6
shared pool                            166      0.01%          1434       7
cache buffers lru chain                146      0.01%           336       3
messages                               135      0.01%             0       8
session allocation                     113      0.02%             0       5
row cache objects                       86      0.00%             0       4
enqueues                                75      0.00%           624       5
latch wait list                         48      0.08%             1       9
session idle bit                        47      0.00%             0       1
undo global data                        14      0.00%             0       5
multiblock read objects                 13      0.00%             8       3
sequence cache                          11      0.00%             0       8
dml lock allocation                     10      0.00%             0       3
transaction allocation                  10      0.00%             0       8
list of block allocation                 4      0.00%             0       3
modify parameter values                  2      0.03%             0       0
process allocation                       1      0.02%             0       0